Windows XP may be eXPired, but it still accounts for the dominant position over the operating system market in 2006. On the verge of Windows Vista's general availability, Windows XP accounts for a market share of 85.30%. While Microsoft is turning its face from XP and prepares to label it as obsolete, Vista's predecessor has grown from 79.90% in January 2006 to over 85% in December.

And although Microsoft has made Windows Vista available to the company's Software Assurance customers via volume licensing starting with November 30, 2006, the adoption rate of the operating system has been timid to pick up, to say the least. Windows Vista increased its market share by just 0.1% since August 2006, and is now at 0,16%, according to statistics made public by Market Share by Net Applications.

In 2006, Microsoft has also experienced a market loss on Windows 2000 and Windows 98. The Redmond Company has discontinued support for both operating systems, and consequently Windows 2000 has dropped from 8.75% in January 2006 to 5% in December 2006, while Windows 98 fell from 4.07% to just 1.77%. But Microsoft's loss is Microsoft's gain, so to say.

Mas OS is down 0.05% in December 2006, compared with January, but MacIntel has grown 1.52% in 2006. In this context, the former users of Windows 2000 and 98 have upgraded to Windows XP, as this operating system has experienced the most consistent growth in the past year. This is both good and bad news for Microsoft. The 5.4% of the market that has deployed Windows XP in 2006, from Windows 98 and 2000, are very unlikely to upgrade again in 2006 to Windows Vista. Microsoft's latest operating system will undoubtedly make a dent on the OS market come its general availability on January 29, 2007, but this depends on the Redmond Company's capacity to educate consumers to upgrade not only from XP to Vista but also at a hardware level.