Have you used blogs to teach English?

I've been teaching over 20 years, and I've read many research reports that using blogs to teach English is good for students. Could anyone comment on this? Were you successful, and if yes, how did you do it?

In Malaysia, blogging is still very new especially in teaching. That's why I'm doing a little research to find out what people from other countries think, and what my own students think about this idea. Many of them have personal blogs, though.