Microsoft is expected to release a beta three version of its next Windows Server, code-named Longhorn, as a community technology preview (CTP) in early March, industry sources say.

The upcoming CTP would be the first public milestone for Longhorn because it will be more widely distributed to partners and customers. Microsoft quietly released a CTP in December to select partners, and the Redmond, Wash., software giant previously said it would release a beta three version in the first half of 2007.

Now that Windows Vista and Office 2007 shipped this week, Microsoft is turning up the heat on its server complement, according to one industry observer. "Beta three will be a CTP soon," said the source, who pegged the current release date as March 7. "February is all about Vista/Office launches."

Longhorn is slated to feature an integrated virtualization hypervisor, enhanced support for branch offices and integration with Vista. "The bright spots are virtualization, [designed to] kill VMWare especially on 64-bit hardware, and manageability, [designed to] kill Linux in branch office deployments," the same source said.