O'Donnell also speculated that the Windows XP effect hasn't been as large as expected -- and thus not noticeable in its regular shipment tracking -- because more users are upgrading in place, eschewing new PC purchases to instead replace XP with Windows 7 on their older hardware.
"We've been hearing that a fair number of people are upgrading in place, something that didn't really happen with previous cycles," said O'Donnell, adding that PCs bought in the last three to five years, the typical replacement cycle for corporate PCs, are able to run Windows 7. "That's different than in previous [OS] changes, when you really had to have new hardware to upgrade."
There is an enormous number of PCs running Windows XP around the world. According to Web analytics company Net Applications, 37% of all personal computers ran XP in June, representing an estimated 570 million machines. Microsoft recently put that number at a much smaller 160 million, but did not reveal how it arrived at its figure. Even Microsoft's smaller number is gigantic, equivalent to more than two quarters of global PC sales at the current rate.
In a talk at this week's Worldwide Partners Conference, a Microsoft executive said the company expected that 10% of all PCs would still be running XP come next April, a percentage much lower than outside analysts' estimates, which have been as high as 25%.
Net Applications' statistics, meanwhile, hint that XP's presence will be even stronger than analysts anticipate: If Windows XP's current rate of decline continues, the aged OS will still power nearly a third of all PCs in April 2014.
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