This week Microsoft's own CEO Steve Ballmer stepped on stage at Build 2012 and let it be known that they'd sold 4 million Windows 8 upgrades in the three days it'd been on the market. Compared to what Apple has asserted with their install base for their own desktop operating system OS X Mountain Lion, this number might not seem quite so impressive - by percentage of installed base, that is. If you consider how many installs of Mac there were compared to how many people upgraded to Mountain Lion against the number of installs of Windows there were compared to how many upgrades there were to Windows 8, the difference is staggering.
According to Microsoft back in December of 2011, they had an install base of 1.25 billion Windows PCs - that includes all versions of Windows. It was also asserted back then, according to business insider, that 500 million Windows 7 licenses had been sold in the last two years (again, this was reported in December of 2011). Interestingly enough, Ballmer also let it be known that 670 million machines are now running Windows 7, that falling relatively in-line with the idea that Windows 7 adoption has been slowing down since Windows 8 was announced.
Apple on the other hand has slightly different numbers as far as OS X installs and upgrades to Mountain Lion, their newest system. Back at WWDC 2012, Apple let it be known that there were 66 million installations of Mac on the market.
Ballmer announced that 4 million Windows 8 upgrades had been sold in the three days since it'd been launched. In the same amount of time, Apple announced more than 3 million OS X Mountain Lion upgrades. If you take the total amount of machines with Windows installed on them and compare it to the upgrade numbers for Windows 8, you get about 1/3 of one percent of the total. If you take the total amount of machines with a Mac OS on them and compare it to the Mountain Lion upgrade numbers, you get 4.5% of the total.
The rate of adoption between these two ecosystems is drastically different - which do you consider more successful? A better question might be: do you consider the adoption rate to be more important, or the total number of machines that now work with one system or the other?