I work at a college and we're in the midst of building out our new Exchange 2010 environment under vSphere. As opposed to our current single-server, single-point-of-failure Exchange 2007 setup, we're moving to a highly available configuration under Exchange 2010. Even though Exchange 2010 supports hosting mailbox, hub & CAS roles on a single server, doing so negates the ability to use both database availability groups (mailbox role) and network load balancing (CAS role) simultaneously due to conflicts between Windows NLB and clustering components. As I'm not that interested in building out a four server Exchange 2010 environment - we don't need it - based on advice from Henrick Walther, we're purchasing a Kemp load balancer - the virtual appliance variety. We've already imported the new virtual appliance into our vSphere environment but do not yet have the unit configured. When we're done, I'll report back on progress and operational success. Our eventual intent is to use the Kemp appliance for Exchange 2010 initially, but we'll also use it to provide some necessary redundancy for our campus web portal.
My goal at Westminster College is to virtualize everything that can be virtualized. With it's reduced I/O demands and virtualization-friendly nature, Exchange 2010 is the first tier 1 application that we're virtualizing, but it's not the last. Later this year, we'll be evaluating a move from SharePoint 2007 to SharePoint 2010 and making a decision as to whether or not to maintain SharePoint as a physical infrastructure or move it, too, to virtual systems.