Criticker's rating system is out of 100 points but for each user it scales ratings into tiers (deciles) 1-10. So for someone like me who watches lots of movies that I sort of know I'm gonna like (thanks to Criticker!), most of my ratings end up in the 70 to 100 range, but I still have 5 tiers in that range. The wide range allows the system to adapt to a user's biased view of the scale. Also plenty of users simply keep their rankings from 0-10.
Criticker gives recommendations in two ways. First it predicts my ranking for a movie. So I can just browse unwatched movies and filter them however I like and then sort by how Criticker expects I will rate them. It is actually scary how predictable I am.
The other method of recommendations is to browse users who have very high correlation to my rankings and see what movies they've ranked highly which I have not seen. This might be the best way to find movies. It also seems to be the key to how the expected ratings I mentioned above are computed.
No doubt one of the things that keeps Criticker running so well is a community of serious film buffs. It makes it easy to find movies I would have never heard of otherwise (foreign, limited release, shorts).