"If I target the end of 2012 to get XP out then you have your migration window," he says. "Organizations really need to be poised to do a lot of migrations on new machines and some existing ones in 2011 and 2012. That will be the mainstream of the migrations."

Silver says Gartner's recommendation is a conservative one that provides a 15-month buffer before XP support ends on April 8, 2014. Mainstream support for XP ended in April 2009, just a year after XP SP3 shipped.

Microsoft for its part told XP users last month (MAY) that if they are just starting to test Vista that they should switch to Windows 7.

Silver recommends users in that boat switch only if it means less than a six-month delay in their current planning. "You don't want to lose momentum. If you have already done lots of testing or might be set to deploy you should continue with Vista," he says. "One of the big issues here is that Vista is a difficult decision politically at this point, but the folks that have migrated to Vista are generally happy."

Hitching the migration horse to the Windows 7 wagon, however, doesn't mean users won't have to take along issues that polluted Vista acceptance.

Applications that were not compatible with Vista won't work on Windows 7. The new XP Mode, available with professional, ultimate and enterprise editions, will give users a bit of a respite, but not a panacea.  

With both Windows 7 (the host operating system) and XP (guest) running on a single machine, users will be forced to maintain and patch two operating systems per desktop.

Analysts such as IDC's Waldman and Gartner's Silver say it's a short-term solution.

"To take full advantage of new enhancements in Windows 7, which is what users are paying for, the app needs to be built for Windows 7," Waldman says. He says XP Mode is likely a one- to two-year Band-Aid.

Users are gearing up

"XP Mode might be the way we get around the fact that some of our institutional apps are behind the technology curve; it could be the answer," says Jeff Allred, manager of network services at the Duke University Cancer Center. He said patch management tools will make it easier to manage two operating systems on a desktop and that XP Mode's administrative considerations are not a showstopper

Allred is in the process of testing Windows 7, which he says is faster, more stable and seems leaner than Vista. "We are much happier with Windows 7 RC than Vista in its full shrink-wrap version," he says.