I have read all the books. I hate to sound like the proverbial d-bag that always has to say the books are better than other media based off them, but they really are. Sure there are a lot of chapter that I think are wastes, but I've never read a more organized series. Martin clearly uses a lot of history as inspiration but the imagination he's put into it is unparalleled. The wait until the next one, is been super annoying. Sounds stupid but it's been one of my bigger fears that one never gets released.
That being said I like the show much better than when it started. I think they killed it last season, especially with the last two episodes. I can't wait to see what direction they head since they are running out of the source material.