Outline of Blog activity for teacher trainees here. It should be on this page with the other one linking here. Maybe one day.
Weblogs for Use with ESL Classes by Aaron Patric Campbell
Class blogs: a better way to teach? by Judy Friedberg. Guardian.
The following three items have been linked from Digitalang.
In the third question Angela is asked, you will hear her interesting references to blogging.
In earlier questions she gives tasked based learning a good wrap.