FTA, “…A senior Red Hat executive today maintained the Xen open source virtualisation environment was not yet ready for enterprise use, despite “unbelievable” customer demand and the fact rival Novell has already started shipping the software…”

Read more at ZDnet…

To be frank nothing beats VMWare at the movement. Enterprise customer needs support and quality. (money or licensing cost comes later). May be one day you will see some xen articles here too 😉