Open source email and calendar solution provider Zimbra got acquired by VMware recently. While there's lots of angles to this story, it also confirms an important part of VMware's strategy: bigger and bigger hardware, running a powerful hypervisor, running thin and optimized OSes, running applications that perform business functions. To enable perfect mobility and ease-of-use, the OS and application will be packaged into so-called Virtual Appliances or vApps. Making the OS thinner is essential for this strategy, and goes against the core beliefs of competitor Microsoft. The succes of the vApp concept will be a deciding factor in the battle between these two giants.