Gartner analysts Michael A. Silver, David W. Cearley and Stephen Kleynhans acknowledge that for organizations running late with Windows 7 it is tempting to forego the OS, but with support for Windows XP ending in April 2014, organizations would be cutting it close.

Microsoft has not announced a general release date for Windows 8, but Gartner believes the company may target back-to-school buyers in 2012 - in which case, the RTM (release to manufacturing) of Windows 8 would likely start around April 2012, a date that would allow general availability by midyear 2012.

"Even if Microsoft meets that very aggressive timeline, independent software vendors and enterprises will likely need nine to 18 months to obtain and test supported applications and plan deployments," the Gartner report states. "That means that most organizations would not be able to start deploying Windows 8 until the end of 2013."

And five or six months after that, Windows XP goes off life support.

At its BUILD developer conference this month, Microsoft , revealing details about the Metro "tile-based" UI, the compatibility with Windows 7 applications, the ease of building Windows 8 apps, and the different devices and form factors that Windows 8 will run on.