But while the 10-year-old Windows XP in U.S. usage share, it's far behind XP worldwide.

Net gives Windows XP a , followed by Windows 7 at 24.17% and Vista at 10.56%. Mac and Linux combine for a little more than 6%.

StatCounter, another market share tracker, puts Windows XP share at 47.32%, but still far ahead of the 30.6% garnered by Windows 7. While the smartphone and tablet markets are being dominated by non-Microsoft operating systems, when it comes to desktops and laptops it is still very much a Windows world.

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in Network World's Software section.