6. Shae
A great many of the fans of the books are upset about the portrayal of Shae in the TV show versus the Shae of the books. Played by Sibel Kikilli, Shae has been given a great deal more depth in the TV show than she has in the books, where she is a rather two-dimensional and transparent character clearly seducing her way into Tyrion's wallet. In the show, however, she's far more likeable, sympathetic and in season two even became someone we root for. This doesn't mean she was miscast, only that the way the character is written is vastly different to that of the books...that said, for me at least, it's absolutely a change for the positive, and adds a lot of value to her relationship with Tyrion.