Danah Boyd wrote a fantastic essay about Facebook and the privacy issues they are dealing with. The thing is, these are issues of their own philosophical devising:

In short, Kirkpatrick argues that [Facebook founder, Mark] Zuckerberg believes that people will be better off if they make themselves transparent. Not only that, society will be better off.

In short, Facebook is forcing on users a level of transparency that may or may not be good for them and society, but is certainly good for Facebook’s bottom line.