Honestly, while I was a fan of the books, I'm not sure what the appeal of GoT is going to be, at least for me. This isn't a judgment of people who do like it, but I'm not sure why I'd get that instead of just playing a d20 Past or Grim Tales game in a homebrew world of my own, or in Martin's world through my eyes. I don't know that we've seen enough of the magic system or the Others so far to have a good basis for mechanics, and while I do like the idea of playing in an all-human political-feuding era with ugly civil war, I don't know why I wouldn't just do that on my own.
Like I said -- not intended as a slam of people who are excited about it. I'm notoriously light on books, and I'm also big into homebrewing, so tie-in books for existing worlds are probably a hard sell with me to begin with.