Just when you thought ...
After shipping Orcas Beta 2 and the TFS Web Access tool, you would have thought that I have enough to play with. The TFS team obviously thought differently. Over the weekend they shipped the first public CTP of Rosario - which is the TFS version after Orcas.
Check out this post by Jeff Beehler with the details. The one cool thing I will point out, which is a common request that I get when I deliver VSTS sessions, is the support for parent-child workitem relationships.
You can download the VPC from here. If you keen on just getting an overview than download the whitepaper.