An article in the latest issue of MIT's Technology Review led me to this fascinating (and short) TED talk by Christopher "moot" Poole, the founder of 4chan.
Since you need to be a subscriber to get the full article, let me summarize the key point: amid all the outright crap that makes up the majority of 4chan, the site accomplishes one important goal: reducing the cost of failure to nothing or virtually nothing.
If you've read Here Comes Everybody, you'll recall that chapter 10 is entitled "Failure for Free." Shirky focuses on the open source movement, but the point is that the cheaper it is to fail, the greater your chances of getting to success and getting there quickly, since failing for free means you're pretty much willing to try anything.
moot's point is that the loss of privacy that results when everything we ever do or say is tied back to our "permanent records" will necessarily result in loss of innovation and creativity.