Reading the Asoiaf books before watching the series is a good thing, imo. You understand everything much more easily, even if it lets you down when you know the original things that happen.
I'm currently in first book. I can't wait to watch , I hear good things everywhere about the show. I'm one of those that must read the books first types.
I don't play now. But I am planning to go back and get them all eventually. I love new leaf so much.