Recommendations should be configurable. Sometimes I'm in the mood for music that I haven't heard before. So I would want a list of music that is of a genre I don't typically listen too, but is highly rated. Also, I may want to check out music that is new to the system, or music that is highly rated, but not by many people (undiscovered).
Off the top of my head, here are some types of recommendations
1) More of what I like: Uses genre/style + ratings, plus people who rate like you
2) More of the genre I like: Uses genre/style + ratings, ignores others
3) Stuff I don't listen to but others like: Other's ratings - your ratings
4) Stuff I might like, but others haven't found: Genre + ratings, low rate count
5) New Stuff I might like: Genre + date added + ratings
We will probably want to end up producing multiple "feeds" of recommendations so that you can check out your recommendations under multiple categories.