Just saw it. It was pretty good, though Jackson is clearly milking the book for all it's worth and there were a few times where it felt like he left the camera running unnecessarily.
Frodo at the beginning didn't bother me at all, clearly those scenes were being used as a framing device. It could have been a bit tighter though, some stuff left for the Director Cuts.
It seems pretty clear where Jackson is going with the Azog plot in the movie. In the book, Azog was originally killed at the battle of Nanduhirion (and that was a good scene), and later his son Bolg shows up with a huge goblin army at the end. Jackson seems to be combining the two characters into one (though apparently Bolg shows up in a later movie) and giving Azog a motivation to want to wipe out the dwarves to justify the Battle of the Five Armies later. In the book the goblins kind of just pop up out of nowhere at the end when news travels that Smaug has died, and they're coming for the treasure. Azog as a Big Bad I think is a pretty good addition to the film. The mid scenes with him didn't bother me when I was watching the movie, but maybe it would be better if he wasn't revealed again until the end as some said.
Radagast is probably there to tie things in more strongly with LotR. Umbran already listed the timeline and backstory, so I'm not repeating all that. It was already speculated that Jackson is going to show the White Council's strike on Dol Guldur, so he's probably setting that up. Here though, the threat that the Necromancer (Sauron) poses is still unknown as Mirkwood is only starting to fall into darkness instead of having 2000 years of Sauron's influence tainting it. In the book though, the Necromancer was infamous enough that even Bilbo had heard of him. I too am curious to know about how Gandalf got Thrain's key since he got it from him about 100 years earlier in Dol Guldur. I was disappointed by Saruman's dismissal of Radagast, I was hoping for "Radagast the bird-tamer, Radagast the fool!" Instead we get a line about mushrooms.
Thorin's resentment towards the elves and Thranduil in particular I think will help in the second movie or early third movie, wherever we'll get the Elvenking plot. I always thought it was strange in the book that Thorin was perfectly willing to give the Great Goblin the lame excuse about visiting his kin in the Iron Hills while he completely clammed up with Thranduil since he had no reason to see him as a complete enemy. Here though, if he thinks Thranduil abandoned Erebor at their hour of need and hates his guts over it, it'll make more sense when Thorin is captured and brought before him. And later in the third movie, his hostility towards Bard and Thranduil after Smaug is killed will probably not make him look as much of a dick as he did in the book.
I liked the stone giants myself, though I thought the whole bit about the dwarves actually crawling on their legs was overdone. The troll scene wasn't bad either
Jackson made decent use of some of the songs that were in the book.
But it was still pretty faithful to the source material, much like the LotR films, once again, the weakest parts tend to be where Jackson notably deviates from the books. But unlike the LotR films were the departures hurt things (Faramir draggin Frodo to Osgiliath, Frodo chasing Sam away, Denethor being a crazed decadent madman rather than Sauron manipulating him into utter despair) some of the embellishments like Azog or Thorin's elf grudge look like they'll actually help the plot later.
