Growing Cold

This thread discusses changes which has radically changed the view of a character: http://asoiaf.westeros.org/index.php/topic/67087-book-spoilers-small-differences-beteween-books-and-show-that-radically-alter-a-character/. The book discussion threads after each episode usually bring this up as well :) Anyways, that's what I came up with on the top of my head ^_^