The Wall Street Journal is reporting that “Facebook, MySpace, LiveJournal, Hi5, Xanga, Digg and several other social-networking sites have been sending data to advertising companies that include: user names or ID numbers tied to personal profiles being viewed when users click on ads, despite promises they don't share such information without consent”.
Advertising companies are receiving information that could be used to look up individual profiles, which, depending on the site and information a user has made public, include: real name, age, hometown and occupation. The companies receiving this data, including Google's DoubleClick and Yahoo Inc.'s Right Media, said they were unaware of the data being sent to them from the social-networking sites, and said they haven't made use of it.
Part of the problem is that most social networks haven't bothered to obscure user names or ID numbers from their Web addresses. After questions were raised by The WSJ, Facebook and MySpace moved to make changes.