Facebook has created a storm of comment around it's change of ts & cs. Techcrunch illustrates the problems of data ownership in social networks perfectly in a post on the subject. Describing the argument of Facebook founder Mark Zuckerberg, Techcrunch writes:
Essentially, he says that the issues are not so cut and dry. When you share your data with someone else, whether it be an email or a photo, it becomes their data as well. You cannot normally rescind data you share with other people in an e-mail. So why should a social network be any different?
But as Techcrunch points out that is tantamount to saying "trust us" - something which becomes harder and harder to do.