The two faces of Bill Gates

There were two Bill Gateses on stage on Wednesday at Stanford University: the philanthropist, and the hypercompetitive Microsoft co-founder and chairman.

While he spoke of prosperity not being a zero-sum game, he also espoused the need for Microsoft to outmanoeuvre rivals such as Apple, Google and Sony.

"We want to either be number one or on our way to being number one," Gates said while speaking at the third annual TechNet Innovation Summit, hosted by a membership of technology CEOs.

Gates, whose comments came during a taped interview with TV host Charlie Rose, showed he hasn't lost any gusto for Microsoft's leadership in technology, despite having announced plans to relinquish his day-to-day role with the company by 2008 to concentrate on philanthropy.

Gates, for example, characterised the success of the Apple iPod as "phenomenal, unbelievable, fantastic". But to put the Zune ahead, Microsoft built features into the media player that the iPod lacks. "We're doing connected entertainment analogous to the Xbox," he said, in the hopes of nabbing new customers and luring those ready to switch.

On Sony, Gates said that Microsoft has traded places with the PlayStation maker because it shipped the Xbox 360 a year earlier than Sony released its competing, and more expensive PlayStation 3, he said. (On its first try, with the original Xbox, Sony beat it to the punch with the PS2.)