According to a new study by Forrester Research, the use of virtual server technologies really took off over the past year, proving that that virtualization has finally past the point where it’s mainly used in testing and development roles.

Some 91 percent of respondents told Forrester researchers that they are using virtual servers for production workloads. That’s up dramatically from 78 percent last year, the report said.

What that means, Andrew Reichman, the Forrester Analyst who principally wrote the report said, is that server virtualization has now developed into a mature market.

“[Now] Infrastructure and operations teams use server virtualization for more production applications, rather than just test-and-development uses,” Reichman said in the report.

Entitled “Storage Choices For Virtual Server Environments, Q1 2011,” the report was co-authored with Vanessa Alvarez, Robert Whiteley, and Eric Chi.

Forrester said it interviewed 104 vendor and user companies that currently use virtualization technology in x86 server environments. Multiple responses were allowed, so the figures add up to more than 100 percent.

“The results show continued trends toward consolidation and simplification and a shift from ‘just making it work’ to streamlining operations,” the report said.

In fact, infrastructure and operations (I&O) executives cited resource consolidation, configuration, consistency, and data protection as the key benefits of server virtualization.

Additionally, I&O teams are expanding x86 server virtualization in order to “increase the overall consistency of their application environments,” the report said.

Among the trends the report identified is that server virtualization has graduated to running more business critical applications. For instance, virtualization of Microsoft SQL Server critical applications grew from 53 percent to 68 percent in the past year. Meanwhile, virtualizing email deployments grew from 29 percent to 51 percent.

Virtualization is yet another market where Microsoft [NASDAQ: MSFT) is well behind the market leader. In the competition to sell hypervisors to the enterprise, that leaves Microsoft’s Virtual Server and its Hyper-V, in a tight competition with Citrix Systems (NASDAQ: CTXS) XenServer for second and third place.

Indeed, Citrix is in second with 17 percent market share, while Microsoft comes in at third with 16 percent. However, neither can come close to challenging VMware (NYSE: VMW) ESX, which has built a mammoth 93 percent share.

“What was once run on separate physical servers with different tools and processes can now be tied together in a common environment, with application monitoring, provisioning, and data protection deployed commonly for all the apps that fall under the jurisdiction of the hypervisor,” the report added.