After a major delay in the early spring which threw off the development cycle of Windows Server 2008, a public beta -- as opposed to a technology preview -- is being released by Microsoft this morning.

You might say the definition of "early" for Microsoft has changed to mean "on time." Last April, an embarrassed company announced a major delay in its roadmap for Windows Server Virtualization, code-named Viridian, one of the key built-in features of the Enterprise edition of its server operating system. Not long afterward, the Viridian team said it would have to cut key features from the product in order for it to make its dates.

The first public beta of Viridian, we learned, would be made available in the second half of 2007, but no more than 180 days prior to the RTM date. With the big rollout party now scheduled for February 27, at an event tentatively titled "Heroes Happen Here," and with the second half of this year drawing to a quick -- and, for many, icy -- close, Microsoft is now making the first beta of what it now calls Hyper-V available for public download, as it says, "earlier than expected."

But after invoking the now-classic Microsoft euphemism "on track" (as in "on track for the first quarter of 2008") to characterize what might appear to some to be a delay to the delay it confirmed last September -- when it affirmed the first public beta would be seen in December -- Microsoft could be surprising everybody by revealing the Hyper-V beta was indeed on track for December after all.

This morning at about a quarter to noon Eastern time, the download link for Windows Server 2008 Release Candidate 1 Enterprise with Hyper-V Beta officially went live. BetaNews FileForum has posted a shortcut to this download.

The RC1 edition of the operating system had already been released, but now Microsoft is providing an alternate edition of WS2K8 RC1 that includes the Hyper-V beta built-in -- Microsoft is not releasing the Hyper-V beta separately. The RC will automatically time out on June 30.

As Microsoft's general manager for virtualization strategy Mike Neil confirmed on his team's blog this morning, Hyper-V retains support for a single virtual OS running on up to 16 physical processor cores simultaneously (the original goal was for 256), with support for 64 GB of addressable memory per virtual machine. This way, the boundaries of a virtualized environment become extremely scalable, with the possibility of a four-way quad-core data cluster -- or multiple servers gathered together to form the equivalent -- housing a single operating system image. Hyper-V can also run in WS2K8's new stripped-down Server Core mode, dramatically reducing the physical operating system footprint for running hyper-scaled virtual machines.

Virtual hard disks can now be inspected and changed outside of a virtual machine envelope, and VHDs created for Virtual Server 2005 R2 can now be ported to Hyper-V. The beta will provide guest operating support for both 32- and 64-bit editions of Windows Server 2003 and WS2K8 for now, though guest support for other brands is said to be forthcoming.

"Microsoft Hyper-V will provide our customers and partners a great platform on which to build their virtualization solutions," Neil writes this morning, "and will provide the best value in the industry. One area I expect to see much more activity in 2008 around virtualized and centralized business desktops as employers aim to better manage employee computing. The datacenter won't necessarily become the home for all desktops, but more mainstream server virtualization technology and management tools will lead to more trials of virtualized desktops."