After watching season two, i am thinking there could (should?) be expansions to this game. Definitely nothing like the lcg, but extra house packs would be plausible for sure. Initially i'd have thought of an expansion per season, but i'm thinking that they'll have to wait for more characters to be introduced.

House Baratheon seems like an obvious option, with Stannis, Renly, Melisandre, Ser Davos (an sons), Saladhor San (sp), etc. It's pretty complete just like Lannisters and Starks.

House Greyjoy and Targaryen are both starting to make sense too with much more coming in season three, leaving House Tyrell and Martell for last.

I'll be blunt: I don't see any point to this game, unless future expansions are planned. The most compelling thing about AGoT's gameplay is the way it encourages multiplayer interaction. Joust (i.e. 1v1) makes for decent play, but Melee is one of the most unique experiences that can be found anywhere in the CCG market, and it's what gives AGoT its flair. I have too much respect for FFG's marketing team, not to expect them to be planning further development for this game.