Stephen Downes, who's been a blogger for a long time, has a thoughtful article in Educause review, "Educational Blogging". The whole thing is well worth reading. Here are a few interesting excerpts:

In one sense, asking why anyone would write a weblog is like asking why anyone would write at all. But more specifically, the question is why anyone would write a weblog as opposed to, say, a book or a journal article. George Siemens, an instructor at Red River College in Winnipeg and a longtime advocate of educational blogging, offers a comprehensive list of motivating factors. In particular, he notes, weblogs break down barriers. They allow ideas to be based on merit, rather than origin, and ideas that are of quality filter across the Internet, “viral-like across the blogosphere.” Blogs allow readers to hear the day-to-day thoughts of presidential candidates, software company executives, and magazine writers, who all, in turn, hear opinions of people they would never otherwise hear.

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Despite obvious appearances, blogging isn’t really about writing at all; that’s just the end point of the process, the outcome that occurs more or less naturally if everything else has been done right. Blogging is about, first, reading. But more important, it is about reading what is of interest to you: your culture, your community, your ideas. And it is about engaging with the content and with the authors of what you have read—reflecting, criticizing, questioning, reacting. If a student has nothing to blog about, it is not because he or she has nothing to write about or has a boring life. It is because the student has not yet stretched out to the larger world, has not yet learned to meaningfully engage in a community. For blogging in education to be a success, this first must be embraced and encouraged.

From time to time, we read about the potential of online learning to bring learning into life, to engender workplace learning or lifelong learning. When Jay Cross and others say that 90 percent of our learning is informal, this is the sort of thing they mean: that the lessons we might expect to find in the classroom work their way, through alternative means, into our day-to-day activities.

Blogging can and should reverse this flow. The process of reading online, engaging a community, and reflecting it online is a process of bringing life into learning. As Richardson comments, “This [the blogging process] just seems to me to be closer to the way we learn outside of school, and I don’t see those things happening anywhere in traditional education.” And he asks: “Could blogging be the needle that sews together what is now a lot of learning in isolation with no real connection among the disciplines? I mean ultimately, aren’t we trying to teach our kids how to learn, and isn’t that [what] blogging is all about?