TEDWoman in Washington, DC: Social Media and the End of a Gender by Johanna Blakly

"People online don't "aggregate" by AGE, RACE, GEOGRAPHY...the "aggregate" by LIKES."

Media and advertising companies still use the same old demographics to understand audiences, but they're becoming increasingly harder to track online, says media researcher Johanna Blakley. As social media outgrows traditional media, and women users outnumber men, Blakley explains what changes are in store for the future of media. .... A MadMen lover, like me.
http://www.ted.com/talks/johanna_blakley_social_media_and_the_end_of_gender.html