Which era was the best-Showa (1954-1975), Heisei (1984-1995), or Millennium (1999-2004)? No one fan can fully agree with one another on this.
What's the qualification for a film to become a cult film. Should huge mainstream successful films with cult followings qualify? (like Star Wars) Or should cult only apply to obscure failed films that are remembered years after the fact?
The flames burn hot in the debates between the original versions of the Star Wars trilogy and the special editions. Likewise with the original trilogy and the prequel trilogy.
And with the announcement that Disney bought Lucasfilm out to make a seventh movie, you can just tell that the Expanded Universe is going to raise all seven circles of hell in response.
Forget seven circles, they'll make an eigth circle of hell just to raise over this.
And then a ninth, and a tenth, and an eleventh...
The IMDb Top 250 list. There are a few films that didn't make the list, and had their fair share of Fan Dumb, Hate Dumb and Fan Hate in their forums, but when a film actually makes the list, or worse... the Top 10, expect the worst.
Highlander. The broken and divided fanbase of this series is purely LEGENDARY; take ANY issue and you'll be met with about 6(+) different factions of fans who all stick to their own individual continuities and will flame anyone who dares disagree with them/think their version is better/think differently/come up with their own take/etc.
For God's sake, nobody bring up among Sweeney Todd fans whether or not he and Mrs Lovett had sex. It's just not worth it. Not only will you be screamed down whatever your viewpoint is, you'll also have to sit through a four-hour exploration of Did They or Didn't They? involving every possible meaning of "my rumpled bedding legitimised" the universe has to offer. This is despite the fact that Word of God says they did in no uncertain terms. Even if you all eventually come to an agreement (not likely!) you will certainly feel the burn of spending (as this troper did) better than forty minutes discussing the sex life of a serial killer. Even if he is played by Johnny Depp.
It doesn't help that there are so many arguments for and against - Sweeney wouldn't have gone to bed with anyone other than Lucy, OR he might have done, but he doesn't get kicks from anything other than murder after the Epiphany sequence, OR he did have sex with Mrs Lovett to drown his sorrows, OR he did because hey, he's a guy and guys enjoy sex no matter what their mental state is... the list goes on and on.
You are only allowed to like either the Pre-Lord of the Rings films Peter Jackson made, or only the films he made after Heavenly Creatures. You are not allowed to like all of his films, under any circumstances. Ever. Yes, that's right, there are flame wars between Peter Jackson fans over whether only his early work was good or only his later work. And neither side is willing to see eye-to-eye.
This baffling attitude comes from his older fans thinking that he "sold out", and that the Lord of the Rings films are long and boring and don't showcase his talent well. They're also prone to calling his newer fans 'kids' or 'noobs' during debates over which of his films are good.
Also, his newer fanbase may be more fond of the Splatter films he made early on. They tend to think his older fans are snobs.
Either way, you have to pick a side. Appreciation for all of the man's work is unthinkable and blasphemous.
Avatar. Now let's all calmly walk away and move on with our lives.
Awards. Academy Awards mostly. Even the announcement of the nominations can spark a flame war whether the movie/director/actor/whatever deserved it, or whether someone else was snubbed.
In fact, the mere mention of The Dark Knight, regardless of your opinion, is enough to start Fan Dumb and/or Hate Dumb tearing at each others throats. Casual comic-book movie fans could never be more embarrassed.
Whether or not the narrative of World War Z could have worked for the movie, and whether or not the film is a good adaptation (or a good film on it's own), the running zombies, the PG-13 rating, the complete jettisoned political angle from the book etc. Either way please let's not get into it.
ANY highly regarded modern (not the classics, those are off limits) Speculative Fiction film. Basically if Horror/Sci-Fi/Fantasy films are highly rated by critics it's probably polarizing among people on the net. Usually within the target demographic too. Some of it seems to be jealous snobbery (from genre fans), mixed in with Sci Fi Ghetto elitism, from people who hate said genre films. Probably the only time those two groups find common ground.
Especially horror fans, This is a fanbase that acts as if there hasn't been any good horror movies since the 1980's (exceptions being foreign horror) and will defend even the worst 1980's horror film simply because it came out then.
Among black movie goers there's the debate over Romance Comedies (or any other type of comedy) vs Dramas. Some see the former as Uncle Tom Foolery, while some sees the latter as depressing sap fests, that show blacks as impoverished criminal stereotypes living miserable lives, and having miserable relationships. Both genres seems to be the antithesis to the other. Also bring up Tyler Perry For Massive Damage.
To that end... Tyler Perry, Tyler Freaking Perry. Tyler is polarizing even among black audiences for widely different reasons. He gets criticism from both genders (though black women are mostly supportive), and the general black populace is bitterly divided over him. Though some think the dissenters are just a very vocal minority. Some of this over laps with the comedy vs drama in black movies debate mentioned above.
Man of Steel has caused many a flame war just by simply existing. As a relativelyDarker and Edgier reboot, it was inevitable that it would pit old-timers against new fans, self-styled purists against the "everything's got to be modernized" crowd, and so-forth. And, while this may be a character known for being a nice guy, the flame wars have been incredibly acerbic. The Internet Movie Database message boards for Man of Steel seemed to get nastier and nastier with each new trailer.
The predecessor Superman Returns also lead to a wealth of flame wars with defenders of the film often accusing people criticizing it of just wanting a generic action film.
What qualifies as a box-office flop, you wouldn't believe the hand wringing over such a trivial matter.