Microsoft Corporate VP of PC, Tablet, and Phone Joe Belfiore

It’s a well known fact that Microsoft Corp’s Windows 8 and Windows 8.1 operating systems haven’t caught on nearly as fast as their predecessor. And indeed, Windows 7 is still by far the most popular OS around, but the later versions are finally gaining some ground, achieving a 15 percent market share for the first time, according to NetMarketShare.com.

Windows 8 is now running on 5.88 percent of all PCs in the world, while the newer Windows 8.1 now powers 10.92 percent, adding up to a 16.8 percent market share between the two. That’s an increase of about four percent from what NetMarketShare gauged in September. Much of the impetus came from Windows 8.1, which rose by 4.25 percent, whereas Windows 8 saw a slight increase of 0.29 percent.

Surprisingly, those gains didn’t come at the expense of Windows 7, which also increased in popularity. It’s market share grew by 0.34 percent to 53.05 percent, making it the most popular OS by some distance. But this month could well be the last in which it grows – just yesterday, Microsoft announced it was going to stop selling Windows 7 to OEMs, which means that once the old stock has sold out, most new computers you’ll see will only run Microsoft’s latest OS.

As for the venerable old, now unsupported Windows XP, it’s still the second-most popular OS around, but only just. Its market share dropped by a massive 6.69 percentage points to 17.18 percent. NetMarketShare says this was probably driven by ‘back to school sales’, with a raft of students buying new machines for their studies.

This will be encouraging news for Microsoft, which has been pushing for people to upgrade from Windows XP for some time now. Nevetheless, it may just be a tad concerned that the Windows platform as a whole has lost ground – Mac OS X was the biggest gainer, growing by 0.67 percent to 7.05 percent overall. Meanwhile Linux was a loser, slipping by 0.23 percent to a 1.41 percent overall share.

NetMarketShare gets its data by monitoring some 160 million unique visits on over 40,000 websites, measuring user market share. For those who wish to follow usage markjet share, head over to StatCounter, which looks at more than 15 billion page views and comes up with significantly different results.

photo credit: Skakerman via photopin cc