I believe many people are introducing Web logging into their classrooms — this is exciting and reassuring, as I plan to integrate it into my introduction-to-humanities-computing class next spring. I’ve been a student in a course that utilized Web logs, and plan to fully integrate discussion of the Web writing experience into classtime discussion. This is something that my instructor did not do; and it ended up falling by the wayside as people got lazy, and as they didn’t get any feedback at all on their posts.
I believe that Noah (of hyperfiction.org) may have used Web logs in an electronic writing class he taught, in a similar way to what you’re thinking. Perhaps you might contact him?