There were rumours that it would be announced at MMS, but I didn't want to comment on them until the announcement was made. System Center Virtual Machine Manager has gone beta.
On the (recently revamped) home page of http://connect.microsoft.com, if you click Connection Directory or See all Connections you'll find
System Center Virtual Machine Manager
That's exciting news. If you're working on Virtualization and would like some assistance drop me a mail - ideally with the word "Airframe" in the title and I'll give you some information about a support programme which we're running.