The development of Windows Vista may have put Microsoft back a cool six billion dollars, but that's just the best $6 billions that Bill Gates has ever spent. And the amount is nothing compared to the impact that Windows Vista is calculated to deliver to the market. According to data made public by IDC, Windows Vista is in fact worth a tad more. How much? Well, just a mere $120 billion.

Back at the beginning of January 2007, Bill gates was bragging about the money Microsoft had put into Windows Vista: "Best $6 billion I ever spent. You don't need to feel bad for us in terms of the profitability of the Windows business. Did we learn? Yes. … It's pretty exciting to see how the things we learned will let us do even better."

The Microsoft Chairman was present at the 2007 International Consumer Electronics Show in Las Vegas at that time. Well, yesterday, during an address at the Windows Hardware Engineering Conference (WinHEC) 2007 in Los Angeles, Gates revealed an entirely different figure, taking about the ever increasing range of devices available to the public.

"So the ecosystem is a key here. Of course, one element that we bring to that is this Certified for Windows Vista logo. It's very important that we set a bar for the devices that are really using the new simple installation, the new security features, and that's what that's for. IDC just did a study showing there will be over $120 billion of economic impact because of the innovation that come around the Windows Vista platform. And that's pretty exciting to see that taking place, and then to see what users do, and go on with that. So our logo program is stronger than ever, and a key thing for users to see which peripherals they should buy for their [Windows] Vista machine," he said.

The $120 billion figure comes from a research study that Microsoft commissioned to IDC, titled "The Economic Impact of Microsoft's Windows Vista and Windows Server 2008 in the U.S." IDC estimated that the IT ecosystem around Windows Vista and Windows Server 2008 will generate no less than $120 billions in 2008. Now, IDC are long-time Microsoft partners, and, in the past, the Redmond Company pressured IDC for more "aesthetic" studies, bending the reality to the advantage of Microsoft. So the $120 billion have to be taken with a grain of salt.

"The impact of Windows Vista and Windows Server 2008 will reach far beyond Microsoft," wrote John Gantz, chief research officer and senior vice president of IDC. "Overall, the advent of Windows Vista and Windows Server 2008 will help local economies grow, improve the labor force, and support the formation of new companies. In addition, the indirect benefits of using newer software will help boost productivity, increase competitiveness, and support local innovation."