Import doesn't work for me.
Do you know how your model compares to Cinematch's SVD? Does your model use only books rated highly or also include low rated ones?
Netflix used to have a great recommendation engine based on what you liked/disliked. It included all of their members ratings. They had a contest in which they offered $1M to anyone who could improve their algorithm by 10%. The winning team used some kind of customized version of Singular Value Decomposition. The algorithm is public.
I think it is essential to use the negative ratings.