But that doesn't mean there are 100 million Windows 8 PCs in operation.
That number is largely made up of new Windows 8 devices that rolled off an assembly line. It includes any still sitting in boxes in a warehouse, reports Computerworld's Gregg Keizer.
Plus, when an enterprise does buy any Windows 8 PCs, Microsoft's enterprise license gives it the right to "downgrade" the operating system to any other version of Windows that Microsoft supports, like Windows 7.
Microsoft knows how many Windows 8 devices are really being used, but it's not saying.
So Keizer came up with a creative way to estimate how many are in use. He took the total number of Windows PCs Microsoft says are in use, 1.4 billion, and the percentage figures supplied by Net Applications. Net Applications counts how many PCs are on the Internet.
In April, Net Applications found that 4.2% of all Windows PCs it saw on the Internet were using Windows 8 and/or Windows RT.
He came up with 58.6 million Windows 8 PCs using the Internet last month.
That's really not a terrible number.
But it's not a good one either because it points to the fact that maybe millions of Windows 8 PCs are sitting on shelves.
Worse still, quarterly PC shipments are in decline and "the Windows 8 launch not only failed to provide a positive boost to the PC market, but appears to have slowed the market," said IDC's Bob O'Donnell in a press release.
So all eyes are on Windows Blue, the next version of Windows 8 that will ship next month. Will it be any better loved?
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