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.
From the book, when Bilbo tries to pickpocket a troll, the money purse suddenly says: "Ere, 'oo are you?", leading to him getting caught. It's never explained how the bag can talk, and it never does so again, nor does it get any comment from any of the charactes. And the narrator just states that "Trolls' purses are the mischief".
Also from the book: the stone giants throwing rocks at each other while the party is trying to cross the Misty Mountains. They're never mentioned again in the whole book (except for Gandalf making a passing comment that he'll have to get a "friendly giant" to block up a pass so that goblins can't get through) nor, so far as I can tell, in any part of Tolkien's mythos.
Recycled Script: In The History of the Hobbit it's pointed out that Thranduil the Elvenking and his hold in Mirkwood is closely derived from the original conception of Thingol of Doriath (Tinwelint of Aranor) — which also explains his distrust of dwarves. This isn't obvious to people who are only familiar with the published Silmarillion, because the final version made Thingol and Doriath much richer and less earthy and sylvan. However, Tolkien added a Discontinuity Nod to this when The Silmarillion does mention that Thranduil lived in Doriath in his youth and modelled his own kingdom in Mirkwood on it.
Unfortunate Implications: After The Lord of the Rings was published, Tolkien once said he partly modeled his Dwarves on the Jews, based on both peoples being exiles from their original homelands. Dwarvish was also modeled after Semitic languages, and the Dwarves continued to preserve their own language and culture while living among different cultures, much like how Jews have done. However, stretching his words and applying them retroactively to The Hobbit leads to some questionable passages:
''There it is: dwarves are not heroes, but calculating folk with a great idea of the value of money; some are trickery and treacherous and pretty bad lots; some are not, but are decent enough people like Thorin and Company, if you don't expect too much."
However, besides ignoring the gap of some decades between these statements, this assumption fails to take into account that: The Hobbit was scarcely connected to Middle-earth when it was first written as a private fairy-story, as opposed to what it finally became, and that dwarfs of Norse mythology and European folklore already had the traits Tolkien used for his dwarves. As Tolkien wrote in a letter:
"Mr. Baggins began as a comic tale among conventional Grimm’s fairy-tale dwarves, and got drawn into the edge of it - so that even Sauron the terrible peeped over the edge."
Characterization Marches On in The Lord of the Rings, since Gimli and the dwarves are clearly heroic despite their prejudices, which Gimli in particular overcomes. The dwarves of The Silmarillion are also portrayed as more heroic than the ones of The Hobbit, which they predate.
One may also consider his response to a publisher in Nazi Germany who asked if he had any "Aryan blood" before they could consider publishing his books. Tolkien's answer could be boiled down to, "No, and neither do you. In fact I regret to say I am not descended from the tribes of Israel."
But to play devil's advocate: Pre-WWII England (heck, probably pre-WWII lots of places) had a distressingly high amount of casual anti-Semitism and Jewish stereotyping (the works of Agatha Christie and H.H. "Saki" Munro provide some examples) and Tolkien may have taken on local attitudes before learning better.
First, Pan's Labyrinth/Hellboy director Guillermo del Toro was announced as director. With his sheer imagination, penchant for unusual creatures, and being One of Us, there was massive fan rejoicing... until two years later, when MGM's money issues and previous directorial commitments forced him to step down, amid rumors that the whole project might be taken out of New Zealand, or even scrapped altogether. But then, just as things looked bleakest, Peter Jackson was announced as the "new" director for the live-action Hobbit using sets from The Lord of the Rings and creatures designed by Del Toro, that MGM's new owners have greenlit the project, and that the production will be staying in New Zealand after all. And once again, there was much rejoicing.
Not only is Benedict Cumberbatch in the movie — as Smaug, no less — but they arranged the filming so that he and Martin Freeman could be in The Hobbit without interfering too much with the filming of Sherlock.
Base Breaker: 48 frames-per-second. Not just a base-breaker for fans, but potentially a base-breaker for cinema itself, if the Cinema Con write-ups are to be believed. Many commented that it presents a huge change in viewing experience.
The Scrappy: This seems to be the case for a character named Tauriel, despite little being known about her besides the fact that she might be an elven warrior maiden and possibly will be played by Evangeline Lilly. And Peter Jackson stressing that no, she will not be romantically involved with Legolas.
The opinions are divided on this matter; some are reminded of a TV production due to the higher frame rate, but others have found the high picture quality appealing, or just a matter of getting used to.
The major problem is that it looks too good, to the point that every other part of the film(the sets, the make-up, the special effects)look incredibly fake. For a film that follows up something as cinematic as The Lord of the Rings, this isn't a good thing.
It must be remembered that the clips shown at CinemaCon were still very much an unfinished product, with a lot of colour correction and CGI elements missing. The critics universally enjoyed the "Riddles in the Dark"-sequence, which incidentally was also the most polished portion of the preview.
They Wasted a Bunch OfPerfectly Good-Looking Characters: According to pictures from Entertainment Weekly, they've cast a lot of good-looking actors as Dwarves, who are then going to be buried under wigs, prosthetic makeup and capes, unless Dwarf fashion decades before LOTR was radically different.
Judging by Fíli and Kíli, not all Dwarves are inherently scruffy.
Del Toro did a lot of preproduction work including designing creatures and color scripts that might not even make it into the finished films, although The Other Wiki says he's still collaborating with Jackson, Fran Walsh, and Philippa Boyens on the scripts.
David Tennant as Thranduil is now an example of this, sadly.
Although any fans of Pushing Daisies should be glad to see Ned the Pie-maker is reportedly our new King of the Elves.
Retroactive Recognition: The animation was sneered at the time as "Japanimation". This was before Studio Ghibli (which was, incidentally, formed by several Studio Topcraft alumni)...
So Bad, It's Good: For some. Others find it enjoyable on its own merits, despite some questionable stylistic choices (chiefly involving the wood-elves).
The wood-elves are almost universally agreed to be Grotesque Gallery. For reference, these are the people Legolas belongs to.
Bilbo himself could be described as Ugly Cute as well. He looks much younger and more jolly than most everyone else, despite looking Little Orphan Annie if she grew up to become an old lesbian.
What The Hell, Casting Agency?: The very Teutonic Otto Preminger (primarily known as a director, though he played one of the versions of Mr. Freeze from the Adam West Batman) as Thranduil.
These being totally random happenings due to the Interactive Fiction being Nintendo Hard. Bilbo can get eaten by the Trolls while Gandalf watches without comment.
The wood-elf in Mirkwood that simply locked you in prison will also arrest various enemies. Like the Balrog.
