The largest deal breaker for MS VM will never be fixed.
Your VM's run on Windows, subject to the never ending slew of security vulnerabilities. At the very least you need to down all of your VMs to patch once a month, some months multiple times. A typical VMWare host runs for years if not its entire life without ever rebooting. I have never seen a Windows host run for more than a few months without a memory leak or something requiring a reboot. Compared to Xen, VMWare, Hyper-V is like building your home on a foundation of sand. I pity those who think this is a business worthy product.
Biting the hand that feeds IT
