To truly understand the devolution of privacy that drove my decision to abandon Facebook, you need only look at this post by Matt McKeon, which leads in:
However, Facebook hasn’t always managed its users’ data well. In the beginning, it restricted the visibility of a user’s personal information to just their friends and their “network” (college or school). Over the past couple of years, the default privacy settings for a Facebook user’s personal information have become more and more permissive. They’ve also changed how your personal information is classified several times, sometimes in a manner that has been confusing for their users. This has largely been part of Facebook’s effort to correlate, publish, and monetize their social graph: a massive database of entities and links that covers everything from where you live to the movies you like and the people you trust.
I was OK when Facebook only shared information I shared with them, but the creeping integration of Facebook with everything else gives them “accidental access” to way more information in aggregate. In some ways, they get more than Google does now, and that’s pretty scary to me. Just click on the graphic to understand how bad it’s gotten. Event the venerable New York Times has gotten into the act with an article entitled “Tell-All Generation Learns to Keep Things Offline”.