I've really enjoyed David Sifry's multi-part look at the state of the blogosphere. His latest entry is about something near and dear to me- corporate blogging. I'm with him in saying that 5000 corporate bloggers is a small number and we're at the beginning of blogging becoming an acceptable part of corporate policy.
Here's how he defines this group:
These are people who blog in an official or semi-official capacity at a company, or are so affiliated with the company where they work that even though they are not officially spokespeople for the company, they are clearly affiliated.