Nearly 13 years ago, PBS program Frontline aired The Merchants of Cool, a documentary made by writer Douglas Rushkoff that analyzed how big companies were extracting youth culture and selling it back to teens, laughing all the way to the bank. That was long before Twitter, Facebook, Tumblr, and many other sites arrived, dramatically changing not only what we share, but also whos sharing online. Tonight, Rushkoff is back in a follow-up called Generation Like, that examines just that.