So, I learned something interesting in law school the other day. Apparently, if you have the privacy setting for the pictures you upload to Facebook set to "public", then Facebook has the right to use those pictures in advertisements in Facebook, and can SELL those pictures to advertisers to use on and off-line.
My teacher told us a story about a family whose photo was being used by a Swiss grocery store in Switzerland on a billboard. The grocery store bought the photo from Facebook.
Its something to think about. Especially if you're concerned about your privacy, or have the secret desire to be an international model and realize this could be an easy way to have international fame without any effort.