The trailer for season 3 is out:
Some thoughts after the brake.
The biggest change from the books that is openly visible is Tormung joining/leading the raid south of the Wall. Instead of Jarl and the Magnar, who are both not exactly fleshed out characters in the book, Tormund gets some much-needed screen-time, so this is a good decision. We need to be able to identify with the guy and to like him once the Dance with Dragons begins. The problem with this approach is, obviously, the aftermath of the battle of Castle Black. Will he be taken prisoner? Will he escape? I don't really believe they kill him, since that wouldn't make that much sense.
In other news, we get Catelyn talking about killing for revenge, which seems like a little setup piece for Un-Cat later. Joffrey is even more of a dick than we knew, Bran is shooting a bow (wtf?), and oh boy, dragons! Looks real nice. The main job of the Unsullied seems to be to present arms before Dany, so she can turn with a harrowing look into the camera. At least the question where her dragons are seems sufficiently answered.
What are your thoughts? Fire away in the comments.