The Chron's Wired Campus talks about a growing number of professors who are experimenting with Facebook, Twitter, and other social-networking tools for their courses, but some students react in horror to an invitation to join a professor's personal network.  Some professors have coined the term "creepy treehouse" to describe tech innovations by faculty that make their students' skin crawl.  Check out the discussion here.  For a definition of the term and concept of "creepy treehouse," see Jared Stein's blog Flexknowlogy.