I thought the book was bad, but this was something else entirely. Saoirse Ronan, as always, is talented, and knows how to keep you interested. Brian Eno made one hell of a great soundtrack. But both are ultimately wasted because the movie ultimately fails to deliver everywhere else. The movie has no idea what it wants to be, like many have said, but hey, at least PJ didn't keep that one scene from the book in - you know the one. Doesn't mean his version is any less reprehensible, though. Overall, Roger Ebert was right and if I could give this movie zero stars, I would. It's, in my opinion, the worst movie I have ever seen. Even on its own, it's a disgusting waste of potential (the March 2007 screenplay was so much better than the final product) and to treat the subject matter so flippantly leaves me breathless, especially Peter Jackson's remarks about how detractors of his direction should just "go watch SAW" or whatever. Lost all respect for the guy, especially when so many primetime TV shows and movies have managed to depict the subject matter decently enough. If you don't feel comfortable tackling a serious issue, then don't do it. Makes me wonder how Lynne Ramsay would've handled things; probably without all the masturbatory CGI nonsense, that's for sure.
Simply put, watch anything else.