What Facebook knows..

..is not known, not even by Facebook researchers, but it is a lot and offers a unique, first time ever dataset that will definitely create new insights.  

“For the first time,” Marlow says, “we have a microscope that not only lets us examine social behavior at a very fine level that we’ve never been able to see before but allows us to run experiments that millions of users are exposed to.”

from: Technology Review (MIT) - What Facebook Knows

The question, however, always remains: does your behavior (or connections) on Facebook really say a lot? Apparently, according to this (preliminary) research on predicting employee’s job success (based on a 10-minute skim through one’s profile on Facebook). Also, and this might be more interesting for Facebook to make money, and a bit more dangerous for its users: basing your credit value (when you want a loan) on your social network on Facebook.