The Red Hat 6 Beta is out, and there is no Xen in it, only KVM. It can operate as a guest in an existing Xen environment, but it cannot act as a Xen host. This isn’t new news, it was widely trailed, but with the emergence of the Beta, there now appears no way back. Xen and RHEL are divorced.
For much of The Virtualization Practice audience, this may seem peculiar. Why (and even how) could Red Hat turn its back on a world-class Type 1 Hypervisor and run with this peculiar Type 2 thing, that nobody has really heard of, and that has such a low profile that people even confuse it with a monitor/keyboard switch also called a KVM?