I largely enjoyed the film myself. It followed the plot mostly faithfully. Jackson did leave the camera running for too many scenes though, he probably could have pulled off a tighter film in 2 hours rather than three, and left stuff for the DVDs.

The clunkiest element was Radagast and how he set up the Necromancer. This was the greatest deviation in the films from Tolkien, and like Jackson's LotR films, the further he goes from Tolkien, the weaker things get. I did like Radagast's quirkiness, but the whole bit about nobody knows who the Necromancer is does mess up the back story (the White Council knows very well it's Sauron at this point), because it raises the question of where Gandalf got Thror's map and key if he hadn't already snuck through Dol Guldur earlier. That though is the biggest problem with the film, and honestly, it's not even a huge problem.

The use of Azog was not a bad approach at all. If anything, it seems like Jackson is using Azog to set up the Battle of the Five Armies later probably in the last film. In the book, the goblin armies seem to almost pop up out of nowhere at the end, but I think in the next two movies, it's going to build to a more satisfying climax later.

Casting decisions were pretty good, particularly with Bilbo and Thorin.

Overall, it's much like Jackson's work with LotR, a decent adaptation of the original work, with some clunky changes that maight not have been necessary. And still a lot more faithful than some book to film adaptations tend to be.