Windows XP lost six-tenths of a percentage point last month, but still accounted for 40.7% of all personal computers, or 44.4% of all Windows machines. Vista also dropped, falling by a quarter of a point to under 6% for the first time since July 2007.
And Windows 7 gained ground, adding about seven-tenths of a point to end the month with a 44.7% share of all PCs and a 48.8% of all Windows PCs. At its current pace, Windows 7 will break the 50% mark next month to become the edition used by a majority of Windows customers.
That trend will likely continue, analysts have said, as enterprises continue to replace their aged Windows XP hardware with newer machines running Windows 7, not Windows 8.
The poor-thus-far showing of Windows 8 doesn't preclude it from eventually thriving, of course. Microsoft is reportedly ready to spend between $1 billion and $1.5 billion on advertising the new operating system, its Windows RT spin-off, and the also-new Windows Phone 8.
At his company's BUILD developers conference, Ballmer made clear that Microsoft was betting big. "You will not be able to pick up a magazine, go to the Internet or turn on a television set without seeing one of our ads," Ballmer told developers Tuesday.
Net Applications measures operating system usage by tracking unique visitors to approximately 40,000 sites it monitors for clients.
Windows 8's pre- and at-launch uptake remains sluggish compared to Windows 7's adoption in 2009. (Data: Net Applications.)
See more Computerworld Windows 8 launch coverage including news, reviews and blogs.
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.
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