I like the Disqus comment system. Threaded conversations are easier to follow and can be selectively ignored, while comment ratings tend to be a reliable measure of content quality. Also, comments left on different Disqus-powered blogs by the same user are consolidated on a unique page, and users ranked by their cumulative comment ratings. It is not clear whether the "2 of 10" rule would be needed if such a system were implemented, given the added functionality and incentives.