Forrester's Johnson said his firm's numbers were similar, although it posed the question differently to enterprises. "We asked 'What are you deploying now on new PCs?' and enterprises are saying the 76 percent are deploying Windows 7. But 16 percent are still going with XP," said Johnson.
"When we ask them what they'll be deploying 12 months from now, their answer is Windows 7, with 60 percent, Windows 8, at 26 percent, and Windows XP, 3 percent," Johnson continued. "But enterprises are notoriously optimistic about future deployments, so I'd say that by the time it reaches retirement, XP will still be on 15 percent to 20 percent of PCs."
That's actually lower than projections run with Net Applications' data, which estimates the percentage of PCs worldwide running each version of Windows. If the trend tracked by the measurement company over the last 12 months holds true going forward -- not a certainty; XP's decline has accelerated in the past year by about 8 percent -- more than a quarter of the planet's PCs will be running XP in April 2014.
Now that's staying power. But not a smart strategy for enterprises, Johnson and Silver said. "If they haven't started migrating from Windows XP at this point, they're far behind," said Silver. "They need to get their act together."
Both Gartner and Forrester have recommended, and continue to recommend, that organizations still running Windows XP migrate not to its successor, Vista, or to the brand-spanking-new Windows 8, but to 2009's Windows 7. "There's safety in numbers," Silver noted. "Would you rather be on Windows 7, where everyone else is, or with the 20 percent of those running Windows 8 [in 2014]?"
The two research firms have urged the XP-to-Windows 7 migration on clients for over two years, once it became clear that the latter was stable, successful -- meaning it would be widely supported by third-party developers -- and secure.
Microsoft has said exactly the same, although that drumbeat, once loud, has quieted considerably as Windows 8 moved towards final.
But as Silver said, firms that have left things to the last minute may be in for a world of hurt. "If [an enterprise] hasn't made any progress toward Windows 7, the time to test, verify and move from XP in just 18 months, well, that has a low probability." Even a year after the 2014 deadline, up to 5 percent of enterprise PCs could still be running XP, said Silver. Among the worst offenders in that potential camp: health care.
"Health care is one of the worst," said Silver, "simply because so many vertical market health care developers drag their feet so much." The image of a hospital, doctor's office, even a dentist's, running an out-of-support operating system isn't reassuring.
Johnson was a bit more bullish on the chances of firms winning the race. "Yes, it's still possible," he said. But to pull it off in 18 months, an organization will have to dispense with an attritional strategy -- where only new machines are deployed with Windows 7 -- and tackle an everything-at-once chore.
Companies, or even consumers, who continue to think XP is "just good enough" to handle their computing needs can take steps, of course, to reduce some of the risk of running an out-of-date OS.
Gartner has a 10-item list it uses when it talks to clients who won't, or can't, leave XP. "They have a number of choices, they can buy Custom Support from Microsoft, they can move applications that require XP to a Remote Desktop Services Server, they can segregate XP PCs on a separate network," said Silver, ticking off three.
Custom Support is the name of the after-retirement support plans Microsoft sells to businesses to cover some products, including Windows. Among the benefits of Custom Support: Microsoft continues to provide security updates graded as "critical" for a product, say XP, after it exits general support.