I started writing out a comment on the somewhat heretical notion that biasing search results against AdSense click throughs would probably be a strong predicter

I started writing out a comment on the somewhat heretical notion that biasing search results against AdSense click throughs would probably be a strong predicter for spam detection, but the comment got long enough that I folded it into a blog post: http://news.ycombinator.com/item?id=2074621 http://news.ycombinator.com/item?id=2074621