After repeated delays, Microsoft has finally made its grand entrance into server virtualization ahead of its latest target release date. The company on Thursday released its Hyper-V hypervisor to the Web, to be followed by its addition to Windows Update on July 8.

By packaging Hyper-V with Windows Server, Microsoft hopes to reverse the head start competitors like VMware and Citrix have been able to gain over the past few years while Microsoft developed its technology. "If you know Windows, you know how to install and run Hyper-V," Bill Laing, VP of Microsoft's Windows Server and solutions division, said in an interview.

Originally slated to be released along with Windows Server earlier this year, Hyper-V had been pushed back 180 days from the release of Windows Server 2008, or early August. Since being released as a beta in February, Hyper-V has been downloaded more than a million times, and Microsoft had about 250 participants in its more intensive early adopter program, including dairy manufacturer Land O'Lakes, The Scooter Store, and online scheduler HotSchedules.

Even though Microsoft estimates the total number of virtualized servers worldwide stands at less than 10%, the company has its work cut out for it. Many companies have begun planning for or carrying out their virtualization strategies, and since Microsoft was late to the game, often those initial plans rely on someone else like VMware.

That means Microsoft will have to work aggressively to make up for its competitors' head start. The company has plans to extensively ramp up the training of its sales people, including sessions at several upcoming Microsoft sales conferences. In the next few months, Microsoft will also hold a number of events to highlight virtualization, much like it held a series of launch events for Windows Server 2008 earlier this year. "Without [the release], it was hard to start talking up what we can do," Laing said.

Along with integration with Windows Server, other Microsoft selling points include price and performance. A test by Microsoft storage partner QLogic found I/O throughput with Windows Server 2008 and Hyper-V was around 90% of throughput on a physical machine, while reports on competitive virtualization products had found throughput closer to 50%.

Following Microsoft's release of Hyper-V, the company will offer an updated version of System Center Virtual Machine Manager sometime in the fourth quarter. Today, Virtual Machine Manager allows IT admins to monitor and manage legacy Virtual Server instances, but not Hyper-V. The new version will include management support for Hyper-V and VMware ESX, while a version to follow will also manage Citrix XenServer. Another tool, the Microsoft Assessment and Planning Toolkit 3.1, to be released in July, will act as a planning guide for those looking to build out their virtual infrastructure.

For Microsoft, server virtualization is just one piece of a larger data center automation vision it calls "dynamic IT" and but one element of a much broader virtualization strategy that also includes desktop, application, and presentation virtualization as well as management, which Microsoft labels a necessary enabling technology. With many of those other pieces already in place, Hyper-V fills one of Microsoft's most glaring holes.