If you thought you had a private profile via Facebook/Twitter/etc., you're a fool. If you thought your emails were private via Gmail/etc., you're a fool. Anything you get for "free" comes w/a price and, nowadays, they're selling you your own emails right back to you. Not the worst idea in the world but I may want to enjoy more than I already know and like, if you know what I mean. So, throw me a curve ball once in awhile, why don't you, my dear data aggregators. Sell me something different. Tell me something new. Okay? Bottom line: turn me on to what you like and be true and keep your private stuff to yourself - offline.
http://www.nytimes.com/2012/02/05/opinion/sunday/facebook-is-using-you.html