Google’s mission has always been to organize the world’s information, and it has sought to do so algorithmically, crawling out into the chaos and trying to make sense of what it finds. Facebook has engineered incentives for people to do the heavy lifting — creating, gathering, and organizing information into the FB ecosystem. Powerful, granular privacy settings (starting with the basic notion of ‘friends’) empower users to create information exclusively for FB’s ecosystem, which everyday is becoming more elegantly structured. This is a big week for Facebook.

Further reading.