These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Avengers Forever was meant as an Author's Saving Throw for the reviled "Crossing" arc, and along the way it simplified the Kang/Immortus connection so that future writers would not have to worry about it. Not that future Avengers writers have made use of Immortus anyway, and Kang was killed off by the next writer to use him.
Several attempts to upgrade the team for the nineties were hated by fans: the Wasp turned into a weird monster◊ (or whatever), Thor with chains and a naked chest, several characters with leather jacks, Deathcry... and let's not remember more. They tried to fix all this by sending the characters to an alternate universe in "Heroes Reborn". The fix was even worse than the original problem. So they aborted the whole Heroes Reborn thing and gave the title to Kurt Busiek, who sent the whole "nineties" stuff to the trash bin and restored the classic Avengers.
My Real Daddy: Roy Thomas; Stan Lee and Jack Kirby may have created the title, but Thomas created two of its major recurring villains — the Grim Reaper and Ultron — and introduced a number of ideas, characters, and tropes to the franchise that are used to this very day.
For Quicksilver and the Scarlet Witch, being members of the Brotherhood of Evil Mutants. For, what, 2 or 3 issues before resigning?
Scarlet Witch has a lovely new one in the form of "No More Mutants". Those three words have come to more or less define her character and direction, to the point that it's rare that any aspect of her life other than the Decimation is brought up. Does she even have a brother anymore?
For some time, the Black Knight, Iron Man or the Avengers in general were blamed for the Nega-Bomb that destroyed the Kree Empire (which was not their doing), and the execution of the Supreme Intelligence (which was their doing).
One-Scene Wonder: Pilot Marko appears for about five pages in Secret Avengers #17, and you are about to read every word he's ever spoken, but he steals the book.
Protection From Editors: Brian Bendis, whose tenure on the title has seen him being able to do as he pleases, which has not been received favorably by all.
This has changed though, if Avengers Vs X-Men, Siege, The Heroic Age relaunch of the classic adjectiveless Avengers book, and "Avengers: The Children's Crusade" are any indication.
They Changed It, Now It Sucks: Basically every single line-up change in the fluid roster has gotten some criticism, but Rob Liefeld's "Heroes Reborn" stand out in terms of negative feedback. The line lasted for only 12 issues, and Liefeld was fired even sooner than that.
What Do You Mean, It's Not Political?: 1960s, there is a special comic book character. A black superhero, named "Black Panther". What do you mean that it is not a veiled reference to the Black Panthers? No, really, it is not: Stan Lee and Jack Kirby created the character first. There was even a brief attempt to rename the character as "Black Leopard", to escape from the confusion, but it was short lived.
According to "Comics Should Be Good", it's actually just a coincidence that the two have the same name and became prominent at the same time.
Despite the name, the crossover Operation Galactic Storm has no similarity to the contemporary Gulf War, codenamed "Operation Desert Storm"
The Woobie: Carol Danvers. First she got powers during the explosion of a Kree machine, became a super-hero, and joined the Avengers. Everything was fine... and from there, down she goes. First, she is abducted, drugged and raped by the son of Immortus, who left her pregnant to be "born" on Earth (long story...). She returned, and the evil Rogue stole her powers and memories: Charles Xavier helped her to recover her memories, but not her emotional link to them. Then she was abducted by aliens, who unleashed great power in her, and she became Binary, but she lost this power as well. Once more with just the power of Ms. Marvel ("Warbird" by then), she joined the Avengers. But her refusal to point her loss of power (which almost led to disaster in battle), and her alcoholism, got her court-martialed and expelled from the Avengers. The Scarlet Witch created an alternate reality where she was the greatest super-hero... but things got back to normal, and she's just another super-hero of the lot. She returned to the Avengers, only to witness their breakup during Civil War. She took the side of Tony Stark, and had to hunt her old friends... and then, Stark was replaced by Norman Osborn, and she had to join those Avengers she was hunting. Even worse, Osborn included Ms. Marvel in his team... who was actually Moonstone using her first costume.
Wasp, though she crosses into Iron Woobie: Her dad died, to kick things off, but she didn't let that get her down too much. Then she joined a superhero team only to be regulated to Distressed Damsel roles and ignored due to being the weakest member of the team. Then her personal chauffeur starts making advances on her until eventually trying to kill her and Hank or her money; said chauffeur, it turns out, being Whirlwind, a villain that constantly kicks her ass when they battle, who's since developed an obsessive crush on her. Then she marries Hank, only for him to be in the middle of a psychotic break that is partially her own fault, eventually resulting in a painful string of events that involve her getting slapped across the face and knocked to the floor, forever turning her into a poster child for domestic abuse in comics. THEN, she spends the next bit of time recuperating from that and dealing with a messy divorce and, when her and Hank start to patch things up, she's attacked and almost raped by Whirlwind, who's crush has turned him into an obsessed psychopath. Then, after not being allowed to do anything for a while, she's used as a Sacrificial Lion during Scret Invasion. During which, she's secretly lost in the Microverse, fighting for her life.
Alternate Character Interpretation: Between Thor and this movie, Loki's tactics change from "Silvertongue" to "ranting villain with an army" and his eyes change colour (green to blue). That and some of his dialogue with Erik Selvig about their experiences with the Tesseract could be read as him also being under coercion from the Tesseract/Staff, if one wanted to do so.
Anti-Climax Boss: Years of superhero movies have taught viewers to expect that a final battle between The Avengers and Loki would happen towards the end of the movie. It doesn't happen quite that way.
Award Snub: Neither Disney nor Paramount created a For Your Consideration... Oscar campaign. As a result, no one from the cast and crew received nominations, except for the visual effects artists. The victory of Life of Pi in Visual Effects left the Avengers ultimately empty-handed.
Cliché Storm: It wasn't lost on several critics and movie goers that The Avengers, for all of its praise, hardly broke new ground in superhero movie storytelling (especially compared to The Dark Knight and Watchmen). It's more than a bit predictable, and every convenient plot twist unfolded in the way most people would expect after viewing one too many superhero flicks. Still, because The Avengers blended the best elements of superhero movies together, this is an exceptional case of Tropes Are Not Bad for many.
Draco in Leather Pants: Go on, look at Tumblr. Search for Loki. We dare you. The fangirls have gone nuts about Loki ever since the first Thor film.
To the point that some have said, without a single trace of irony or sarcasm, that he's the real good guy and all his misdeeds should be automatically forgiven. Yes, this includes his attempted genocide of humanity.
A character interpretation shared by Tom Hiddleston, incidentally. He thinks Loki needs a big hug.
Dude, Not Funny!: Several of Tony's comments that make light of Steve's tragic situation ("You're spry for an older fellow," "I guess you missed a few things doing time as a Capsicle") and Thor's line about Loki being his adoptive brother, to some.
This can also be attributed to the fact that the two are perfect Foils. Dark Knight Rises is bittersweet, theme-driven, introspective, gritty and realistic, while The Avengers is triumphant, runs on action scenes and Rule Of Cool, and fully embraces the Magitek fantastical world of the Marvel Cinematic Universe. This means that which film is objectively "better" is a very tricky question to answer because they are so entirely different.
Some fans complained about Black Widow's lack of a Russian accent. She identifies herself as Russian in the film but talks about having been raised in the United States and then spending a lot of time abroad. Additionally, she's an international spy who has mastered multiple languages. So obviously, she can speak with a perfect accent. If she couldn't, she wouldn't be very good at her job. The comic character has never been described as having a Russian accent and in fact, has passed herself off as an American citizen more than once so it is safe to say that the original version speaks English with a US accent.
Some fans weren't happy with Cap's line about Thor ("There's only one God, ma'am, and I'm pretty sure He doesn't dress like that"), claiming that Joss Whedon was having a case of religious Writer on Board. Putting aside the fact that Cap has always been a deeply religious Christian (and therefore such a line isn't out of character for him), Whedon himself is a staunch humanist who once derisively referred to the Abrahamic God as "the sky bully."
Loki fans from Thor absolutely hate the film for Loki's depiction, attacking everything from him acting far more villainous than in Thor -forgetting that, even in Thor, he had no respect for humanity (sending an Asgardian WMD to kill as many people needed until it took out Thor), and attempted mass genocide (his attempt at destroying Jotunheim and its people) and he has spent a year or so in space, alone- and for getting his butt kicked by each member of the team at least once -forgetting that he only directly fought three of them (Cap, Thor, and Hulk), during which he utterly kicked Cap's ass, put up a decent fight against Thor, and, you know, was fighting Hulk; and as the villain he's supposed to get beaten by the heroes- which they decry as Badass Decay-forgetting that Loki was a Non-Action Guy in Thor and the simple fact he actively fought the team makes this a case of Took a Level in Badass- to smaller things, like him 'forgetting' that Hawkeye's arrows explode-something not shown until the final scene, after he's freed of his control, and would have no reason to know of- or being sexist-which, while not shown before, he wasn't exactly shown to not be- and being outsmarted by Widow-who is also a gifted Chessmaster, and even afterwards in doing so allowed his plan to work as planned- to just about anything. Accentuate the Negative is in full effect.
Loki-Chucks: The ten-second thrashing that Loki receives at the hands of the Hulk, during which he is whipped around by one ankle like nunchucks.
Fetish Fuel Station Attendant: Scarlett Johansson's Black Widow full stop. Where to begin? In her first scene she's tied up. Then she breaks out by kicking the ever-loving shit out of three guys while jiggling noticeably. She wears a skintight Spy Catsuit which she revealed in interviews she wasn't wearing underwear underneath (for temperature control purposes) and is usually 1/4 unzipped. She carries a gun. She does all those acrobatic jumps, twists, turns and such...so many fetishes served in one character, and Joss managed to get a barefoot shot of her in stockings into the film. And of course, it's Scarlett Johansson.
Fridge Brilliance: Loki gets his mouth sewn shut in Norse mythology after a trick with the dwarfs goes awry. At the end of the movie, there's a muzzle over his mouth as he's taken away to Asgard.
Considering that it took going unconscious to break Loki's Mind Control, take a look at Hawkeye and Selvig throughout the movie. This is especially true for Selvig—he never changes clothing and starts noticeably growing stubble. It's clear that Loki is forcing those he controls to stay awake constantly in order to complete his project. It also explains why Hawkeye looks worse and worse. It may also have affected him in the fight with Natasha.
Steve: Big man in a suit of armor, take that off and what are you? Tony: Genius billionaire playboy philanthropist.
He's Just Hiding: Coulson is speculated to have actually survived his encounter with Loki. The fact that Nick Fury was later revealed to have at the very least lied about where his Captain America cards were located, as well as his actor stating that Whedon has him booked for more Marvel movies also leads credence to this.
Back in Iron Man 2, the last thing Nick Fury said to Tony Stark before they meet again after the finale is "I've got my eye on you." Which was after assigning Agent Coulson to monitor him, whom we hear Nick Fury refer to as "my one good eye" in this movie.
Complaining about Shows You Don't Watch: On Rotten Tomatoes, one critic called the film out on being 'cynical'. Despite the fact that, one of the many criticisms people make about the film is that its too idealistic. Compared to the previous films, Joss Whedon works, and other recent superherofilms, it's probably one of the most upbeat works in the genre.
The UK DVD/Blu Ray release is undergoing this for two specific reasons.
The editing of Agent Coulson's death, by digitally removing the tip of Loki's spear penetrating the other side of his body when it was present in the theatrical release. This isn't helped by the BBFC commenting that they were unaware of any changes to the film, and any such changes would need to have the film undergo classification again; and Disney UK's denials of any editing taking place, and that everyone who saw the film is mistaken when they claim that the tip of the spear was visible in theatres, despite the BBFC classification explicitly mentioning the scene as being in the film.
Music to Invade Poland to: Technically, Loki's invading Germany, and only as a distraction. Still, two seconds after he starts a buttkicking rampage set to the tunes of Richard Wagner, he's pretty accurately compared to Hitler.
Harry Dean Stanton as the security guard. "Son, you've got a condition."
The old German man who stands up to Loki.
Thanos. One non-speaking appearance in The Stinger, but to some comic fans, he's one of the most memorable parts of the movie.
The Galaga-playing SHIELD agent, despite only appearing for five short seconds.
Rescued from the Scrappy Heap: The Hulk. Two previousattempts to bring the character to the cinema screen proved somewhat lackluster, the role got recast once again, and the character had already developed a reputation of being the most boring of the team. However, a combination of Mark Ruffalo's performance and clever screenwriting*
And the hilariously awesome "Puny God" scene
turned The Hulk into an unexpected favorite of the movie, making the possibility of a new Hulk film much more likely. Might be one of the fastest turnaround times for this ever. Shortly before release, producer Kevin Feige said there were no plans for a Hulk movie. Shortly after release, it was let slip that a Hulk movie may be in development for 2015 and that Mark Ruffalo had signed on for six more films.
Really, it's that Mark Ruffalo's interpretation of the character is that Bruce Banner is a normal guy who's got issues instead of the emotionally-stunted, severely repressed individual of the previous films who was constantly scared that he'd flip out over everything. Likewise, his version of the Hulk isn't that he's a barely controlled rage monster; his casual Offhand Backhand of Thor after they brought down a Chitauri Leviathan and his smackdown of Loki shows us that the Hulk is really just an irritable jerk (albeit with a heart of gold) who just happens to have superpowers.
Unfortunate Implications: Lampshaded, in the commentary, and then averted for that very reason. During the Kneel Before Zod scene in Germany, Joss Whedon realized the unfortunate implications of all the Germans kneeling, and so he added the old man to defy Loki, thus turning it into a Crowning Moment of Awesome. He also made sure people started getting up after Captain America arrived, so that Cap wouldn't be standing above them but with them.
Thor's quip about Loki being adopted offended an adopted person. 
Ship-to-Ship Combat: Due to the large Slash fandom and heaps of Ho Yay, pretty much every Avenger or SHIELD agent in the film has being attacked for being in the way of a pairing with one of the others.
Due to the Platonic Life Partners relationship between Hawkeye and Black Widow, and the very Ship Tease like moments between the two, comic book fans that ship Hawkeye with his ex wife Mockingbird have gotten fairly aggressive towards Widow. Likewise, fans of Widow and Hawkeye have been tossing unending heaps of hate towards Mockingbird for the crime of the two breaking up.
On the Natasha side of things, comic fans who are invested in her current relationship with Bucky Barnes are also bitterly against the movie fandom shippers of Clint and Natasha. This heated rivalry exploded with the announcement that the next Captain America movie will be Captain America The Winter Soldier, and will feature both Bucky and Natasha, with no news of Clint being involved.