From the summary:
"Summary: “Velocity” is a distributed in-memory application cache platform for developing scalable, available, and high-performance applications…"
White paper: http://msdn.microsoft.com/en-us/library/cc645013.aspx
PS.: It sounds like the kind of thing that could be used by some big systems I know. I’ve heard they have implemented the cache themselves… If only they knew Microsoft was coming with this.