Hi all, I've been working quite extensively with kvm on CentOS 5.3 lately. If you are interested in the latest rpm of kvm-kmod-2.6.30-rc8, qemu-kvm-0.10.5 and libvirt-0.6.4 you can temporary find them here:
http://update.nethesis.it/kvm/
I've had no problem so far using these packages. Feedback is welcome.