Windows 8 powered almost 10% of all devices running Microsoft's OSes last month, even as its uptake pace slowed, according to analytics company Net Applications today.
Meanwhile, Windows XP's decline continued as customers, prodded by the upcoming April 2014 support deadline, again ditched the veteran operating system in droves.
Windows 8's user share of all computing devices running Windows, a tally that includes Windows 8.1, the update slated to ship in two weeks, jumped to 9.8% in September, Net Applications said. The 1.4-point gain was down from the record one-month increase set in August, but nearly double the OS's 12-month average.
The August-September surge of Windows 8 may have been driven by sharp back-to-school sales of touch-based notebooks, which accounted for a quarter of all sales from June 30 through Sept. 7, the NPD Group said last week.
About one out of 10 devices running Windows 8 ran the Windows 8.1 upgrade last month, said Net Applications. Microsoft launched a public preview of Windows 8.1, the restart to the problem- and perception-plagued OS, in June. The update will hit the Windows Store, where it can be downloaded by current users, on Oct. 17, and hit retail on Oct. 18, when many of Microsoft's OEM (original equipment manufacturers) partners are expected to unveil and start selling new hardware.
Microsoft will launch its revamped Surface tablets several days later.
Windows 8 also increased its lead over Windows Vista, the oft-derided flop from 2007, when each OS's share was compared 11 months after launch. At that point in its release cycle, Vista accounted for 8.5% of all Windows PCs. The gap between Vista and Windows 8 -- 1.1 percentage points in August -- widened in September to 1.3 points.
Windows 8 will certainly pass the 10% mark of all Windows PCs this month.
Part of the rise of Windows 8 must also be credited to the decline of Windows XP, the 12-year-old operating system slated to drop off Microsoft's support radar next April.
For the second month running, Windows XP shed several percentage points of user share, ending at 31.4% of all personal computers worldwide. That was equivalent to 34.6% of all systems running one Windows flavor or another.
The rapid two-month decline of Windows XP hints at the final push to dump the "walking dead" OS that many analysts predicted would accelerate as the April deadline looms. Microsoft will issue its final security update for XP that month; after that, while the operating system will continue to run, it will do so in an increasingly dangerous environment because Microsoft will not provide patches to the general public for any vulnerabilities, critical or otherwise.
Some security experts have speculated that cyber criminals will unleash attacks in the months after April 2014, having saved up their "zero-day" vulnerabilities and associated exploits until the deadline has passed.
Using the trends in Net Applications' data, Computerworld now predicts that XP will power between 18% and 26% of the world's personal computers at the end of April 2014. The lower number assumes that the accelerated decline of the last few months continues, while the higher user share assumes XP's drop-off resembles the more stately 12-month slide.
Microsoft has aggressive plans for deprecating XP, although it has not shared any new specifics. "We have plans to get [XP's share] to 13% by April when the end-of-life of XP happens," said Kevin Turner, Microsoft's COO, during a half-day presentation last month in front of Wall Street analysts. "This has been a major and multi-year initiative for us, and one that we've worked very hard on to make sure we can execute towards."
While Windows powered nine out of 10 personal computers in September, Apple's OS X -- the foundation of its desktop and notebook Macs -- ended the month with a record 7.5% user share. Linux, which has never made good on its loyalists' hopes that it would dominate desktop PCs, finished September up slightly, to 1.6%.
Net Applications measures operating system user share by tracking unique visitors to approximately 40,000 sites it monitors for clients.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is email@example.com.