Virtualization for "dummies"

Have you heard that one of the hottest IPO lately is VMware ? What does this company do ? "Virtualization". Whats that ? May be a concept that is hard to grasp initially, but it is an area with great potential to simplify and minimize IT infrastructure. As someone involved in building a RHIO, IT infrastructure costs are a hugh issue and can be a barrier in forming RHIOs and HIEs.
Check this Dell blog item (complete with a video presentation) for a good introduction on Virtualization. Basically, from the dell website on virtualization (not meant to be an advertisement for Dell BTW),

"Virtualization allows you to run multiple applications and operating
systems independently on a single server. Administrators can quickly move
workloads from one virtual workspace to another - easily prioritizing business
needs while maximizing server resources"