I have barely used Twitter. I have less than a dozen tweets, have a few dozen friends who follow me and a few dozen who I follow and yet this is what TwitterSheep can tell about me:
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I have been marginally more active on Facebook (again primarily accepting friend requests or sending out friend request, pretty lame - I know). And see how well TouchGraph can describe me and my network.
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With so much information about each of us and how we are connected, what we like/dislike, our political views, our brand preference, institutions we are affiliated with, places we have worked, lived and travelled to and a long list of other things... it is only a matter of time before Facebook, Twitter and other figure out how to monetize it.
Don't you think?