Microsoft has taken some first steps in this regard, they pointed out; for example, Windows Server 2008 can be preconfigured based on roles. "That's a step in the right direction, but it's still fairly superficial," said Silver. What's needed is a radical change in architecture that goes beyond packaging DLLs, he added.

The move to server-agnostic applications is still in its infancy but will soon have a major effect on enterprise computing. The legacy applications won't go away, even if the exciting stuff is being done on Internet-based apps, they said. But it won't stay that way. Today, 70 percent to 80 percent of corporate applications require Windows to run, but the Gartner analysts expect a tipping point in 2011, when the majority of these applications will be OS-agnostic, such as Web applications. "Sometime in the middle of the next decade, Windows will be playing a much less important role on the desktop," MacDonald said.

Virtualization changes our view of what operating systems are. Virtualization starts offering levels of abstraction between the OS and the hardware, pointed out the analysts. The hypervisor is taking on some of the role of what the OS did. "Is this the time to redraw some of these lines?" asked Silver. "For us in IT, the interjection of these new layers helps introduce fluidity, and lets us better manage IT."

And Yet, Gartner Says: Don’t Skip Vista

All of these points don’t necessarily mean that your enterprise should skip Windows Vista entirely. Although half the Gartner clients they surveyed don't plan to begin Vista migration until the second half of 2008 (the same clients who represent 2.5 million PCs and, in 2006, confidently said they'd get going with Vista in the second half of 2007 or the beginning of 2008). "We don't recommend skipping Vista," said MacDonald. They do, however, suggest that enterprises adopt Vista by attrition (such as when buying new computers that have it preloaded). That's not because of Vista's virtues but, said MacDonald, because Windows 7 is scheduled to be released in 2009 or 2010, and you don't want to wait until 2012 for deployment.

The analysts recommended that in the short term, enterprises assess the range of Windows OS types and instances in their infrastructure and determine their company's own tipping point for OS-agnostic applications. In the next year, they said, IT managers should evaluate where various virtualization technologies and OS-agnostic apps can provide early advantages.

Should you consider other operating systems? (It's not an unusual idea.)