Every single critic should realize, before critiquing this movie, that they are critiquing the book. That's what Jackson has done here, flawlessly. He didn't miss a song (that I can note 3 were sung), he didn't miss a detail, and he added in the appendices which gave MUCH more depth into the LORE of the actual universe of MiddleEarth. If you haven't read the book and you are giving it a negative review, then good for you nobody cares. This is the first film I've ever seen that is 100% loyal to the book, hell the only thing I noticed missing was Gandalf talking to the Wargs on the other side of the mountain (yes they can talk people who don't read boooks).
Adding in the buildup to Lord of the Rings along the way made this even better, with strong ties visa vi the Necromancer and the sword returning. It's sad that LoTR couldn't have been done nowadays and followed after this movie with the same cast because it would make this film even stronger.
As a fan, I've loved The Hobbit more than LoTR for a long time now, it was so much more of an adventure and so much less of a love story. I'm sad to see critics flinging crap just to get their names heard, at a movie so beautifully crafted nothing could ever tear it down. I hope the critics will come to their senses.
As for accuracy BY THE WAY, this movie was extremely better than LoTR (Tom Bombadil, like him or not, was placed in that book for a reason, along with every other detail they didn't produce, meeting him is how they received their weapons). So if you're a true fan (not some poser), this movie should make you drool.