I think many of you will be familiar with the story of The Hobbit, but the story in this film if you weren't clued in by its predecessor defers from the book. As I said on Twitter I daresay this is better than the book. We get to see more of other parts of Middle-Earth that were mentioned briefly in the book like Gandalf going to Dol Guldur to face the Necromancer. However there were also changes to the story that were in the book. However I will not say how so I don't ruin anything for you. I don't consider the Gandalf sentence ruining it because if you read the book you know that was mentioned, and you can tell he does that if you've seen the trailers.
The settings in this film are pretty amazing. I'd rather not say anything because I don't want to ruin anything for you. However I will say that getting lost in Mirkwood, according to the movie, is easier done than said. I know that seems odd to say, but when you see the movie you'll understand. I also enjoyed how they portrayed the Lonely Mountain and Erebor. If you have read your fantasy you know that dwarves are supposed to be expert builders. The mountain certainly goes above and beyond that expectation. However it also captures the feel of the emptiness and loneliness that I believe they were trying to give the dwarves.
I also enjoyed the styles they gave the different areas in the movie. Lake Town seemed like a place that one would expect to find in a people living under the hands (or wings) of a dragon: desperate. The people are clearly a shadow of the people of Dale and have had some attempt to reclaim that glory. However due to the few resources they have that is not entirely possible. The elves of Mirkwood forest also have a pretty cool design about them. If someone wanted to use a look that seemed both regal and wild about someone at the same time Peter Jackson and his design team accomplished it. The wood elves are dressed finely yet they are also capable of quick travel through the trees. Very nicely done.
All in all I really enjoyed this movie. I'm sorry if I seemed a little vague, but I didn't want to ruin the movie for anyone who has not seen it. If you haven't seen it and want to I would definitely recommend it.