Integrating Blogs in Online Communities

What makes an online community work? I've become interested in this recently, especially (but not exclusively) online communities that are Virtual Learning Environments (VLEs).

The communities that seem to be successful seem to offer a personal space for the member. This certainly adds to the feeling of involvement that the member has. This is true of the online community for education professionals Tapped In, which provides each of its members with a virtual office. You can link to other offices, and you have a personal filespace (as you would have in a real-world office). All-in-all, it works well, and increases the level of involvement you have in the community.

Another successful online community that offers this personal space is Book Crossing. Each member has a personal page, which they can use to write whatever they want, apart from any standard details they want to share with people. The basis of this community tends to be local, but with the possibility of linking internationally.

Neither of these communities use weblogs, however, although I am sure that we will see more community spaces adopting weblogs as part of their site. There is one I came across (Student UK) which used blogs as the way of linking members together and offering members this personal space, which seems to be one of the keys to any successful online community. Unfortunately, this site has recently run into trouble and has shut down, although it could be reopening if they find a sponsor.

Does anyone know of any other community (VLE or other) that uses blogs as a tool?