Just three years after it was founded, XenSource has gotten itself acquired for half a billion dollars by Citrix Systems Inc., demonstrating the rising value and power of virtualization.

Privately held, XenSource recently announced the release of XenEnterprise 4. In a statement yesterday, Citrix said that the acquisition will allow it "to extend its leadership in the broader application delivery infrastructure market by adding key enabling technologies that make the end-to-end computing environment far more flexible, dynamic and responsive to business change."

The acquisition will also strengthen each company’s strong partnership with Microsoft and commitment to the Windows platform. The acquisition is expected to close in the fourth quarter of 2007 subject to the satisfaction of closing conditions.

“Today is a great day for the virtualization market," said Peter Levine (pictured), President & CEO of XenSource, "because customers will now have a strong alternative that is open, proven and backed by one of the most successful end-to-end software infrastructure leaders in the entire industry.”

“This move is not about competing for the five percent of the market that is already being served. It’s about steering into the 90 percent white space that is wide open, both at the server and in new emerging opportunities at the desktop,” Levine added.