> Making spam unprofitable would be a good first step. Rather than trying to detect whether something is spam or not, just target how spam sites are funded: ads

> Making spam unprofitable would be a good first step. Rather than trying to detect whether something is spam or not, just target how spam sites are funded: ads, analytics, affiliate links, etc and use those as a negative ranking signal. This would be a really interesting experiment: A search engine that ranks websites by the amount of Ads and other spam that they contain.