Good article in Windows Server 2008 virtualization vs. VMware's offering

Although not a development issue per se, virtualization is a topic that developers also need to understand. Even if modern virtualization requires no modifications to applications, developers need to understand the scenarios under which their (.NET) applications are being run.

Speaking of the alternatives, there's VMware, and then there's Microsoft with it's Hyper-V virtualization on Windows Server 2008. A very nice blog article has been written about the combatants. Be sure to check it out.