Everything in seasons one and two were really a setup for season 3.

They will be mostly faithful to the book, but there will be some surprises, too.

Specifically, NO ONE IS SAFE.

But we've known that ever since losing Ned Stark at the end of season 1.

Game of Thrones last supper: http://io9.com/5949671/tyrion-plays-jesus-in-the-game-of-thrones-last-supper

White Walkers concept art: http://io9.com/5949575/game-of-thrones-concept-art-gives-us-a-closer-look-at-the-white-walkers

Reading the book (before the show) Ned being killed was a big, big shocker. It'd be like Aragorn dying in LOTR or Hermione in HP. And my brother's words rang in the back of my head at that moment, "don't get too attached, David, remember that everybody dies."

It's still shocking if you go back and watch it again, even knowing that it happens.

You just can't believe they spent all that time investing in that character, just to kill him so early in the story.

And yes, I think the thing that makes it interesting is the same thing as LOST: no one is safe.

I never watched LOST but that one comment alone makes me want to more than anything else I've ever read about the show.