You might want to take a look at Oxite. It's the content management and blogging engine used to host the MIX conference website and online community.
In their own words:
Oxite is an open source, standards compliant, and highly extensible content management platform that can run anything from blogs to big web sites. We know this because it runs MIX Online.
It's designed to be developer friendly and at first glance looks like a very clean architecture and implementation. I've been toying with the idea of giving my blog a refresh and I have not yet had a chance to take the ASP.NET MVC Framework through it's paces. I think I'll download Oxite and take it on a test ride over the holidays. Stay tuned to hear how it goes.