Meanwhile, Microsoft's Windows operating system, which still commands the vast majority of the computer market, saw a decline of 3 market share points from previous year: the company had 91 percent of the market in September 2007, down from the 94 percent a year ago. Specifically, the company's Vista operating system had about 7.4 percent of the market in September. Net Applications, the report said, attributes the gains to Apple's new Intel-based architecture, which was first introduced in January of 2006. Previous reports indicate that surging Mac sales are expected to beat Wall Street expectations by nearly 400,000 units. Earlier this month, one report indicated Apple may sell 2.35 million iMacs and MacBooks this quarter, fueled by back-to-school shopping as well as a recently refreshed iMac.