Had an interesting discussion today about the pros and cons of profs becoming Facebook friends with their students. On the one hand, profs want to connect with students as individuals --- it makes education more effective, as well as more fun. On the other hand, everyone is entitled to keep their private and professional lives separate, but social networking sites blur the boundaries between them to the point of nonexistence.
Similarly, some people think that students will find an "invitation" to be a prof's Facebook friend as hard to turn down as an "invitation" from your boss to play golf (as in, "Uh oh, if I don't, I won't get the same referrals/references/opportunities as people who do"). On the other hand, a lot of shy people are more comfortable networking electronically than face-to-face.
So, what do you think? Don't do it at all? Create a group called "Friends of Professor X", remind students to make sure their privacy settings (and posted content) are appropriate, and invite them to join that? Something in between? What would you do?