Facebook, MySpace and various other social platforms are now under fire after it was revealed that they have been sending user information to advertisers, specifically user profile information when their sites visitors have been logged in and then clicked on an advertiser link.
According to the Wall Street Journal that user information was sent despite assurances from many major social networks that they would not send that type of identifiable data without their users consent.
Usernames and ID numbers can be easily used to obtain personal information (various demographics) about users. Among some of the largest groups to receive this information have been Google and their DoubleClick platform and Yahoo Right Media. Both Google and Yahoo however are claiming that they were not aware they were receiving the extra user information.