Only just saw the episode - thought it was great. I liked the book concept - I didn't see it coming so when the Doctor suddenly realises he's reading about Rory that was a cool change of tone. Thought the acting was very good considering the temptation to overact with a script like that - I like the Doctor's reaction after reading the chapters, and Amy and Rory's exchange on the rooftop. I kept thinking that I would kill myself in that position for the reasons given in the show, but didn't expect it to go that way.
Flicked through the last few pages: people need to complain about plot holes less. I'd rather have inconsistencies and unexplained things than restrict the show. I do think they could have made the episode a special feature length one though.
EDIT: Also, just realised that when Amy reads ahead, the doctor breaks something - but then the doctor breaks nothing: River breaks her own wrist...