Three years after Windows 10's release, Microsoft's latest desktop OS has finally overtaken Windows 7, which Microsoft released in 2009 and will stop supporting next year.
Net Market Share's December 2018 report shows that 39.22 percent of the machines from which it collects statistics use Windows 10, just ahead of the 36.9 percent that use Windows 7.
The cross-over happened over the month of December, though each version's share of Windows devices has been close throughout the entire year.
Fellow web analytics firm StatCounter reported Windows 10 overtaking Windows 7 last January. The two firms use different methodologies to count desktop marketshare as explained in this piece by ZDNet's Ed Bott.
Another reliable source to compare desktop usage is the US government's analytics portal, which shows systems used to visit government websites.
It reports that 24.9 percent of visitors using Windows are on Windows 10, compared with 13.6 percent who use Windows 7. Windows 10's share of Windows visitors to .gov sites is up from 21 percent last February, while Windows 7's share has declined from 19.8 percent during the period.
Microsoft at one point aimed for Windows 10 to be on one billion active devices by 2018, the year it would have released a major new version had it not switched to Windows as a service.
However, the goal was abandoned after it became clear it would not be achieved, in part due to the failure of Microsoft's Windows Phone and Nokia plans.
Microsoft's latest update on Windows 10 adoption was that it is running on just under 700 million machines, or slightly less than half of the 1.5 billion devices that run some version of Windows.
SEE: 20 pro tips to make Windows 10 work the way you want (free PDF)
While most consumer Windows devices are likely to be running Windows 10, recent upticks in adoption appear to be coming from the enterprise. In October, Microsoft CEO Satya Nadella said more than half the enterprise device installed base was on Windows 10.
Meanwhile, it appears Microsoft has followed its fastest-ever rollout of a new version of Windows 10 with its slowest rollout. According to Windows-focused analytics firm AdDuplex, just 6.6 percent of Windows 10 machines were on the Windows 10 October 2018 Update or version 1809 by December 28.
"October Update is unique throughout the history of Windows 10 updates. While previous updates inevitably shoot up after a month or two on the market, O18U is still lingering near the zero axis on the chart," notes AdDuplex.
The 1809 update of course has been bogged down by a data-destroying bug that prompted Microsoft to halt the update in early October, only resuming its release in mid-November.
It has also been slowly releasing version 1809 to users who manually attempt to download it. As of December 17, Windows 10 1809 was "fully available" to users who opt to get the upgrade manually.
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Microsoft is starting to roll out the Windows 10 October 2018 Update today, starting with Insiders and those ready to proactively grab the new bits.
Windows 10 is getting a big update in its next release. Here are some of the enterprise-centered features to expect in the Windows 10 October 2018 Update.
Plus: Windows 10 October 2018 Update is now available.