I agree fully with the reviewer below. It is a remarkable book and the film had the potential to be magnificent...but unfortunately it isn't near the mark.
There is too much focus on special effects (eg. Jackson showing off) and Susie's heaven which are not the important parts of the novel. There are major themes, scenes and plot lines missed out completely which was a total disappointment (eg. Susie's mother's affair) which is a huge shame. As a result of missing alot out and focusing on special effects as opposed to character development and narrative there seems less to chew on.
What makes this film most disappointing however is the perfect cast is underused. Academy Award winner Rachel Weisz is woefully underrused. I was looking forward to her portrayal, but she isn't given enough screen time. If this adaptation was faithful she would have been brilliant. Wahlberg is impressive, but given too much screen time. Tucci is brilliant and deserved an Academy Award nomination for this role. Sarandon is excellent comic relief and one of the better characters, at least Jackson got her right mostly. Ronan is the best however, effortlessly portraying Susie (it is a disgrace that she wasn't nominated for Best Actress this year), she has been nominated in Atonement for a supporting role, and truly deserved to be nominated again for this if Tucci did. Nevertheless she is very talented and could have an exciting future.
Don't get me all wrong though, I LOVED parts of this film. There is a scene where Susie ends up in her killer's bathroom (which wasn't in the book) which is rather stunning. The acting from Ronan, and special effects here are superb.
The score is awesome too, it is a hauntingly beautiful repetoire which helps the emotional scenes bear weight. I remember especially the scene where Susie's parents are told to fear the worst, it was very dramatic.
So, overall there is excellent acting, and some excellent parts but overall it is a painful disappointment. If Jackson had spent more time focusing on the beauty of the novel, than the beauty of his CGI this film could have been one of the best of the year. Definitely watch it though, I will certainly be getting it as there were some scenes I loved and Ronan is definitely worth watching. Why she was snubbed by the Academy for this I will never know.