Data provided by StatCounter indicates that Windows 7 had an average market share of 40.5 percent in October, up from 39.0 percent in September. Windows XP fell from 40.6 percent to 38.5 percent in the same time frame.
Windows Vista is somewhat stale at 11.2 percent and does not seem to be retreating much these days, while Mac OS X made a jump to 7.2 percent share. Linux has an estimated market share of 0.8 percent.
The market share data released by StatCounter highlights the strong presence of Windows XP in enterprise environments as XP share during the week is on the same level with Windows 7 at about 39 to 40 percent, but dips as low as 35 percent on weekends. Windows 7 climbs to close to 43 percent on weekends.
Last month, Microsoft announced that it has sold 450 million Windows 7 licenses, which keeps it close to 20 million units a month or about 650,000 million licenses sold per day, which is a pace Microsoft has maintained since the launch of the OS two years ago. In comparison, Microsoft in its Q4 2008 report that it had sold 180 million Vista licenses by the end of 2008 - more than two years after launch, if we count in the Express Upgrade marketing campaign that allowed retailers to pre-sell Windows Vista before it became available in January of 2007.
This is according to StatCounter, however, as Net Applications still sees Windows 7 behind Windows XP at 34.6 percent versus 48.0 percent.