Consider this my seconding of everything Marshall Kirkpatrick has to say about writing, owning your main online publishing platform and so on. The entire thing is great and thought-provoking but this sticks out for me:

Maybe there’s something to be said about using a personal blog as a scratch-pad to solicit initial discussion on a draft idea, though, and then taking the polished end-result out to a corporate hosted forum with lots more audience. I wrote a post on our company’s blog yesterday about ways to leverage the experts in your community to collaborate on blog posts and in that post referenced a saying from Google exec Hunter Walk: that you should post to a blog not to show how smart you are, but to solicit feedback from smart people, because that’s a great way to learn.