As a user, I think it would be helpful to know what "for our purposes having the degree of opinion is important" means in a way. Maybe include an explanation-for-morons of your algorithm (or whatever you're using) to give us a better idea what 10, 20, 30... really means.
I understand that highest ratings = similar movies please -and- lower ratings = no similar movies, please
but if I like Lock, Stock, and Two Smoking Barrels and think Snatch blows, how do I rate to keep the Guy Richie suggestions coming, but not to bug me every time Brad Pitt uses a foreign accent in an action film?
what are the thresholds? i pulled that example out of my @$$ just now, but I won't give out so many '60' and '70' ratings if I know (as a user) that keeps a movie/artist in my "similar movies/music please" realm. conversely, I'd give out WAY more '40' and '50' ratings if I didn't think I was being rude to 'OK' artists...
"It's no measure of health to be well adjusted to a profoundly sick society." Krishnamurti