While I'm not really going to cover the entire video, I did find this bit amusing:

Not facebook, not the "b" one, NOT ON ANY OF THEM.

The "b" one being, I'm assuming, 4chan. (Specifically, /b/. Note I'm not linking to it...)

Which I wouldn't have called a social networking site.

But I find it hilarious that she called it "the 'b' one."

And one quick remark: the reason social networking sites don't bother checking people's identities before they show up is because there are six billion people in the world. But for the sake of argument, let's say that only one million people use our social networking site.

How fast can we check identities? If we assume that we can accurately check each identity in as little as an hour.

In that case, it would take over 100 years to identify everyone.

Now we can assume some of that can be done in parallel, so with twenty people verifying identities 24/7 we can reduce that to about five years.

But the point remains: it's infeasible to actually verify the identity of people joining social networking sites.

For most people, it doesn't matter, because no one would bother impersonating them.

So, really, the only people that need to be verified are people who people would bother to impersonate. Which is... hard to define.