Do people have wet underwear for nothing over XEN?
See http://www.redhat.com/promo/qumranet/
<snip> Q: Will Red Hat continue to support and contribute to Xen?
A: Yes. Red Hat will support Xen until at least 2014 (seven years after the release of Red Hat Enterprise Linux 5). We are committed to insulating our customers from changes in the infrastructure components and this is why we created an open virtualization management standard (the Libvirt API). This standard is provided in Red Hat products and has been adopted by a number of other vendors (Sun, Novell, Ubuntu, etc.). It allows customers and ISVs to build virtualization management applications, processes and configurations based on a stable API, independent of the underlying virtualization technology.
Red Hat continues to be an active member of the Xen development community and is currently working on further integration work between the Xen hypervisor and the Linux kernel.
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As far as CentOS is concerned saying Xen is deprecated is jumping the gun. CentOS ships with Xen and as long as upstream supports it, CentOS by extension supports it.
Regards, Vandaman.