This isn't your father's web application.
Traditionally you'd build out this kind of web site with a content management system; either a framework that you'd buy in, or something that you'd roll yourself. It would probably be based on SQL Server
This is a mashup based on Windows Live Services. All the content for the web site, without exception, is stored "in the cloud", either in Spaces, Contacts, Expo or The Silverlight Streaming Service.
Windows Live Services provides a whole host of features, but increasingly it also provides rich programmability. Think of this as the new component model, distributed computing, functionality coming from the Microsoft network and being reused in your own applications.
We're only using Windows Live Services that are publicly available today (although some are still alpha or beta) - everything we do here, you can do yourself. This is leading edge. If you want bleeding edge, see Windows-Live-in-a-Box or talk to a friendly
Windows Live Services Quantum Mechanic.
Yes, we are early adopters. No, it's not perfect, but we believe that there will be fundamental changes to the way that web applications are architected in the coming years and this might be one of the first small steps. We invite you to experiment and
judge for yourself.