So, stop using Facebook if that bothers you. Same comment, re: privacy, goes for GMail, Google documents, Twitter, Yahoo, etc.

The sci-fi author David Brin (a cool guy, BTW, I once went to his house and had a long talk with him) has a good take on privacy (pardon my paraphrasing, but could not find a direct quote): lack of privacy can be tolerated if it is an even playing field. That is, if politician, corporations, etc. all have the same lack of privacy as people.