School-based Social Networking?

I have been a little skeptical about the use of social media in schools. It's not that I don't see the potential benefits for providing a space to practice digital citizenship as Matthew R. Winn lays out in his article in Learning and Leading. Actually, after reading the article, I thought it was a great idea. Create a safe space where students can engage in Facebook-like activities without the potential risks that Facebook and other open social networking platforms can have. It's the digital equivalent of having students practice driving in a simulator.

My skepticism emerges because I'm not convinced that students would actually use it. I've participated in a few restricted social networking sites and, to be honest, I never went to them because they never became part of my routine as have Facebook, Twitter and other social networking sites.

I want to clarify that I see creating an in-house social network as different from using classic Web 2.0 sites
like Ning and Wikispaces. Using these sites, can add a valuable element to instruction. The first time that I assigned students to post on a discussion board on a Google Site prompted a wonderful reaction from the students and allowed some of my quieter students to join in the conversation in a more meaningful way as well as extending our class discussion. Students engage in these assignments because they are homework or part of a class project. I'm not convinced, though, that they create a place for practicing the digital citizenship skills that they will need on Facebook or whatever the latest social networking site is.

So, I'm curious if other schools have taken the plunge that Winn's school has and invested in an internal social networking site and how faculty, students and parents have embraced it. Do students use it? Is it enhancing digital citizenship? Have you noticed changes in other on-line behaviors?