As of last count on technorati, there are 5000 corporate bloggers in the world today. (Link through CorprateBloggingBlog). The operative word here, I think, is count. Surely there are many more corporate blogs (or bloggers) who have not been counted.
And following this link took me to David Sifry’s page where he has an excellent 4-part series on State of the Blogosphere – definitely a must-read…