During his keynote address at the Consumer Electronics Show 2008, Bill Gates revealed that Windows Vista has sold more than 100 million copies since the operating system launched in January 2007. This is 11 million more than XP managed during its opening year.
InformationWeek then pointed out, with the PC market nearly twice the size now than in 2001, that Vista has only captured 39 per cent of the new PC market, whereas XP had captured 67 per cent in its opening year.
Of course there are many other factors to consider, such as XPs predecessor and the increased market share for Macs. So the success of Vista may not be as clear cut as it looks.