The most interesting stuff however, and IMO, was in the Q&A. JT asked George why the Targaryens waited so long to invade Westeros, and he said that mostly they had just been happy to sit on their rock. It was Aegon who had the ambition ... and there had been temptations to go east, rather than west, with various Free Cities trying to lure him to their side on their interminable wars (JT has copious notes, and he'll do a better job -- my PDA went on the fritz and I couldn't copy anything down, but I did video it on the camera and with any luck the sound quality should be sufficient to transcribe any other interesting details). A grand alliance was involved in some fashion.
Oh ... and George doesn't seem to have known that Darkstar isn't very popular. ;) He thought that a "bad boy" character would go over well, since people seem to love the Hound and even Theon Greyjoy so very much. We will probably have to have a discussion about this at the BwB party. ;)