This is directed to K-12, but of interest - he discusses his rubric for social media interaction (note the link to a rubric for blogging in the first paragraph as well).
"By changing their homework assignments from disposable, private conversations between them and me (the way printed or e-mailed assignments work in students' minds) into public, online statements that became part of a continuing conversation, we realized very real benefits."
"Two professors from the University of Westminster in London explained research finding that use of educational technology such as blogs and online questionnaires, combined with personal tutors, could enhance the feedback loop while also making face-to-face communication more efficient."