I just came across a good summary on one of our favorite topics from KM Magazine. It was written by Bill Ives of Portals and KM fame:
I'll forgive Bill for not mentioning BlogBridge :-)
"Blogs are both a technology and a way of communicating. On the one hand, they are nothing more than simple Web sites, often published in the form of a journal, that provide original content, links to other relevant content, simple editing features, comment capability, archiving, search, and security options. This ease of use provides a vehicle for the writer's unedited personal voice, which is considered a defining aspect of blogs. While many uses beyond personal journalism have emerged, the individual voice remains a central characteristic, even in the corporate setting."