See [Bouillon] for working implementation of similar principle (reputation and opinion-aware peer-to-peer wiki).
My vision of large-scale moderation for online forums like UseNet has always been based on the WebOfTrust model. My basic goal is the same as CliffordAdams with his ViewPoint concept: A content-filtering method that tailors itself to each user's needs. --MattBrubeck
This concept is a moderation system similar in function to the one at SlashDot, where posts are rated by readers. Each post has a "score" based on the sum of the ratings it has received, and users can choose (for example) to read only highly-rated posts.
The proposed mechanism, in brief:
One way to think of this is as rating-prediction. The system tries to predict what rating you will give an article which you have not yet seen, based on how you rated previous articles and on how others rate them. How you actually rate it then provides some feedback which the system can use to correct its future predictions. The prediction algorithm can become arbitrarily complex.
Amazon used a system like this for predicting which books you will like, with the idea of selling you more books. A message-filtering system could filter based on your predicted ratings.