The most popular question for the new season is - if it's gonna follow the book closely? Since the second season of The Game Of Thrones added some plot of it's own and changed a bit from the novel, I guess it might be a great idea. Especially since some of the most brilliant characters from the novel, like the sadistic king Joffrey, for example, get killed.
Since they've already been some modifications added to the show that altered the characters, but not the plot, why not go in a new direction? Why would you want the show to follow everything in the book when you may have already learned that Robb Stark gets killed by Frey and gets his wolf's head sewn onto his body? Or that Joffrey gets poisoned? Jon Snow killed? The story could shift a bit.
The 2nd season did some nice alterations with Daenerys' story line. Like the black fat guy instead of a white gay guy who hosted her. Or the part where her dragons get kidnapped. Robb's girlfriends are not the same character in the book and the show, either. Even Joffrey is more of a sociopath in the show and gets extra scenes, the ones where he tortures the prostitutes, for example. The show wouldn't be as predictable, since the fans already know what happens in the book. Oh, and if you don't like spoilers, you probably shouldn't read this blog.