I noticed a blog posting by Daniel Veillard on Fedora People about initial support for OpenVZ being added to libvirt. If you aren't familiar with libvirt, it is an underlying library/API that can be used by higher level tools to create, manage, and monitor virtual machines. libvirt is trying to be technology agnostic by supporting several virtualization technologies. They started off with Xen and QEMU but have since added KVM. libvirt is used by the GUI tool Virtual Machine Manager which first appeared in Fedora Core (now Fedora) but became part of Red Hat Enterprise Linux 5.
Looking at some of the postings in the libvirt mailing list archive for this month, it is mentioned that adding OpenVZ support is a bit different than previous technologies because the OpenVZ tools are already GPLed, "simple and straight forward", and than OpenVZ additions to libvirt "ends up looking very close to the original". I don't know how far away complete support for OpenVZ is in libvirt nor when it will show up in Virtual Machine Manager but I definitely look forward to it... although I doubt it would completely replace vzctl and the other OpenVZ tools for me.