This IDC study reviews the performance of the Windows client operating environment (COE) market during 2005 and provides a forecast through 2010 for Windows 95, Windows 98, Windows Me, Windows NT Workstation, Windows 2000 Professional, Windows XP Home, and Windows XP Professional, as well as full-detail forecasts for Windows Vista client products.

"Leading up to the introduction of Windows Vista next year, Microsoft's portfolio is quickly homogenizing, with Windows XP playing the role of the primary product in the installed base. Yet, even with this high degree of uniformity, we still see the growth prospect for Windows COE shipments to have a 2005–2010 compound annual growth rate (CAGR) of 8.2%," said Al Gillen, research vice president, System Software at IDC. "The 2007 launch of Windows Vista will be an important event, but at this time, we do not see that product causing a significant short- or long-term acceleration of sales of Windows client products."