I’ve kept meaning to link to the EFF’s collection of excerpts from facebook’s privacy policies. They tell a pretty clear story.
I recently deleted my facebook account (having suspended it a few months back) partly because keeping up with its changing approach to privacy, terms+conditions, etc. is simply too much work. Representing social relationships and working out privacy/publicy in that context is always going to be hard, but facebook’s approach appears more and more cavalier, reliant on their users’ confusion and/or apathy.