A little update: I arrived back to school for faculty meetings this week, and found that the school administration finally wised up and blocked access to Facebook, MySpace and a number of other social-networking sites via the school's network. This probably won't stem the tide of cyberbullying--we can't monitor what kids do on their personal computers at home--but at least it relieves the burden of liability a little bit.
Unfortunately, however, cell phones are now allowed back on campus after being banned last year. I expect to spend at least 5% of each class period confiscating BlackBerries. How do my students think I can't tell they're texting? Why are they texting during my classes? Am I a bad teacher? Professional anxiety rears its ugly head.