Leaked HP documents indicate Microsoft has given XP yet another stay-of execution, this time until April 30, 2010 - meaning it will be on the market with not just Vista, but Windows 7.

Microsoft was originally scheduled to finally take Windows XP off the market, after a number of reprieves, in June last year.

The OS is, after all, now eight years old in a market where Microsoft has traditionally upgraded Windows every two years.

Asked at a US analyst meeting whether Windows XP users should upgrade to Windows Vista, or wait for Windows 7, Microsoft CEO Steve Ballmer replied: "If people want to wait, they certainly can”. Mr Ballmer was speaking at a technology conference in Florida hosted by Gartner, which is now archived as a webcast on the research company’s website.