Below is a quote by one of my students about the effect of blogging:
"When I write in my blog, I end up writing more than I started out with. I end up writing something - and it is usually much better than my other writing - that helps me understand whatever it is that I am writing about ... so, writing about Animal Farm helped me understand Napoleon and his tactics."
"Whatever extra there is in me at any given moment isn't fully formed. I am hardly aware of it; it awaits the next book. It will - with luck - come to me during the actual writing ..." (from his Nobel Lecture, "Two Worlds.")
I think that the process of blogging is, for my students, a kind of elucidating experience which generates understanding, which awakens from their dormant state ideas that aren't "fully formed." While all writing is a form of cognitive activity which forces us to think and re-think our views, blogging tends to be more effective than writing in one's notebook because it instantly exposes our thoughts and ideas to a wider audience. What follows is gratification, feedback, discussion. My students (so far) have responded very well to that.