The MSDN and TechNet blogging infrastructure is based on Community Server (based on the old .Text code base). This has served the Microsoft blogging community well, but now that SharePoint supports blogs I know that a lot of people have been curious to see when we would start using SharePoint for Microsoft bloggers.
Today, Lawrence Liu from the SharePoint product team moved his blog over from TechNet to a new domain for SharePoint bloggers. His new site is located here. I'm not sure what the plans are for this infrastructure, but its a pretty cool idea. I've been waiting to see this and hope that we'll see more of our customer facing sites moving to SharePoint in the near future.