How Can Leaders Use Blogs?

In today's educational settings, how can educators use blogs? One good way to use a blog would be to create an online professional learning community. The leader could select a book or article, etc. for the staff to read and then they could participate in blog discussions about the book. This would be easier than setting aside meeting time to discuss the material, but would serve the same purpose as a bookclub. It could also be a different method to get information out to the staff and perhaps to the rest of the community. I'm still a little old school about this kind of communication, but I see that it could have definite possibilites.