I'm happy to say that we've been blogging at my work for the last 3-4 months and it has been well-received. We're using SharePoint as a blogging tool -- not really the normal tool for blogging, but it actually works pretty well. People can subscribe to alerts to a discussion, and you can also sort your discussion by specific categories.
I find that if it makes a nice substitute for email. When you have something to share, but don't want to send an e-mail blast, the blog is perfect. It doesn't clog inboxes, and people can respond at their leisure.
By the way, you should check out the September Intercom article on corporate blogging -- it's a good read.