A soaring demand for data centers crossed with an intense interest in virtualization is leading companies to conclude that, hey, they may need to hire some virtualization experts. The proof is in the job listings. The Dice technology job site now contains some 1,500 listings for folks with VMWare experience, up from just a few hundred last year. While sys admins willing to tackle virtualization basics initially brought it into the enterprise, companies are now seeking more sophisticated skills as virtualization expands into new areas such as as the desktop. Companies may want to consider using contractors and outsourcers, as well as training internal staff, say some experts.