kvm is QEMU with support for the VT Vanderpool or Virtualization Technology. This means you can now run QEMU on CPUs that have the VT instructions and you get a super quick emulated environment. Yay!
Previously to get spritely performance out of QEMU you needed the closed-source KQEMU kernel module. Now you don’t. This interests me because I use QEMU quite heavily with my little screencasting project with Ubuntu-UK. Having a totally Free (GPL) and easy to use method for running virtual machines is essential. Of course there’s Xen but kvm is a great drop-in solution with very little requirements on the host, no replacement kernels for example.
