Yesterday Fedora maintainers sent out an announcement on the fedora-virt mailing list about the availability of a virtualization repository tracking changes in Fedora 13. For you fedora 12 users, this means you can test the latest bleeding edge virtualization features in the soon to be released Fedora 13. To use this new repository, you need to add a file under /etc/yum.repos.d with the following contents and an appropriate filename, for example fedora-virt-preview.repo

[virt-preview]
name=Virtualization Rawhide for Fedora 13
baseurl=http://jforbes.fedorapeople.org/virt-preview/f13/$basearch/
enabled=1
gpgcheck=0

If you already use the virt-preview repository then you only need to update your .repo file. Once your .repo file is in place, issue the 'yum update' command to get the latest packages. For the original announcement on the mailing list see the following link.

http://lists.fedoraproject.org/pipermail/virt/2010-April/002012.html