Of course, there will always be points where my idea of good and someone else's don't jive, but often there are universal quality judgements.

Ahh. Subjective analysis is a portion of our hypothetical equation. Right now it's just the AllMusicGuide rating (1-5 stars.) That might be enough of a subjective "quality" judgement to help things out a little bit. And if you had a penchant for a certain low-rated artist the idea is that your repeated high ratings of that particular artist would outweigh the one-time subjective rating which is just used to provide the initial guess as to how much you like it.