“Combining Exchange 2010 high availability solutions (database availability groups (DAGs)) with hypervisor-based clustering, high availability, or migration solutions that will move or automatically failover mailbox servers that are members of a DAG between clustered root servers, is now supported”.
In other words, The Exchange team heard us, and they’ve added support to install DAG members (on Exchange 2010 SP1) on a highly available virtualisation cluster. That will simplify many virtualised Exchange installations.
Also:
“The Unified Messaging server role is supported in a virtualized environment”.