This article does a much better job of it. The introduction and the first two sections are where she really deals with this, particularly under the "Are MySpace and Facebook Bad?" heading. (Most of the rest is about library marketing and is therefore probably not of interest to most of you.)
Before social networking sites existed we had teens exposing themselves with Web cams, we had teens posting inappropriate pictures of themselves and writing inappropriate things. We had perverts going after young people in chat rooms. And before MySpace and Facebook, teens used the Web a lot. They used it to IM with their friends, to visit online communities they were involved in, to blog, to game, etc. Before MySpace and Facebook, however, there was no one site that was so huge and pervasive and captured the attention of so many teens. It’s hard to point a finger at the Web and say it’s bad for kids and they shouldn’t use it; it’s easy to point a finger at a specific site or a few sites and blame them for everything that’s wrong with young people today.
It's not the site, it's the behavior. And banning the site won't stop the behavior. Education, not legislation. That's my philosophy, too.