There is a great post on the Attensa blog about using blogs within an organization:
If you are running a consulting company, you might have following Worksite types:
• Project Worksites - these are used to exchange information about a specific project
• Client Worksites - these are used to talk about a specific client
• People Worksites - these are like internal resumes that show who is working on what
• Practice Worksites - these are used to communicate amongst a whole team
• Focus Worksites - the only thing that resembles a consumer blog, these are written by a small group and are like internal e-journals dedicated to specific technical topics
This is a very important topic, because this is where blogging shows its real power and begins to replace email.
You don't have to be a large company to use this. A one-person show could have a single blog that updates their clients on project process. Each client would log in and only be able to see "their" posts and any posts intended for everyone.
