The number of IT shops putting server virtualization technology to use in production and pilots surpassed 50% in 2006, according to a survey by Forrester Research.

The research firm surveyed about 1,770 enterprise and smaller companies and found that use of server virtualization grew from 29% in 2005 to 40% in 2006, and the number of firms piloting remained flat at 11%.

Forrester also found that "interest and awareness" in the technology also increased in 2006. The survey shows the number of those aware but uninterested dropped from 23% to 17% in the same time period, and firms unaware of server virtualization decreased from 19% to 8%. About 92% of those responding said they were at least aware of the technology.

Adoption and awareness could have increased due to more commercial and open source technologies available -- and bigger marketing efforts on the part of vendors, Forrester says.

"Server virtualization moved from a niche Unix technology to mainstream use in x86 servers in many firms in 2005," reads the report released this month. "As a result server virtualization market leader VMware has to compete with Microsoft's Virtual Server product and the Xen open source virtualization technology."

Despite more vendor choices, VMware still came out on top as the virtualization vendor of choice among North American survey respondents.