Graziano Sorbaioli pointed out a link to the w3schools.com OS Platform Statistics. The data from their web server access logs shows which operating systems visitors to w3schools.com use.
I wanted to look at the data graphically, so I created two OpenOffice.org charts.
Operating System Shares
OS Platform Statistics - Yearly averages
Not surprisingly, around 90% of visitors run Windows. But Windows usage is declining slowly, from 93% in 2003 down to 88% in 2010. Mac and Linux* are both growing slowly but steadily (Mac faster than Linux). All other operating systems account for only 0.67%.
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