Open source virtualization has been evolving dramatically over the last few years. Incumbent proprietary platforms such as VMWare still hold the throne in many areas but open source competitors are gaining ground fast on their way to ubiquity. Things are a-changing in the land of virtualization.

Right now we have three contenders to the (open source) throne battling it out for supremacy:

• Xen: backed by Citrix
• VirtualBox: backed by Oracle/Sun
• KVM: backed by RedHat