Windows NT is traditionally known for developing software applications for business. But if games are developed for its Xbox console it will signify something more than just the evolution of Embedded NT. It will seal the success of Windows' multimedia API, DirectX, and it will bring thousands of bright programmers into the Redmond fold.
It will also extend Microsoft's command of the programming industry.
Not long ago, PC games programmers paid little attention to Microsoft's operating systems and development tools. They used Dos as a loader, but then "hit the metal" to get maximum performance.
But by putting NT and DirectX into the Xbox, Microsoft is taking Windows-style software development to a large, new audience: games programmers who have previously mainly or only worked with Sony, Sega and Nintendo software development kits.
The company hopes that many of these "spotty oiks" who like to hack consoles will see the benefits of using their new DirectX skills to develop commercial applications for PC's as well.
Some people expect Microsoft to fall on its face because "it doesn't really understand the games business". Failure is certainly a possibility. However, it does understand the software development business, and with the Xbox, it has focused its attention on the software developers it thinks most likely to create great games.
The titles unveiled at E3, the computer games trade show that opens in Los Angeles next week, should tell us whether that strategy is working.
Most of the dealers, distributors and market analysts which form the key audience at E3 don't really care what Microsoft puts inside its Xbox console. Their main concerns are what it will cost, and whether there will be enough good games to sell it.
If Microsoft is successful in launching into the games console market, it will help to change the perception in industry that Microsoft is a PC company, rather than one that - as its updated "mission statement" claims - supports any device used in any place.
Jack Schofield is computer editor of The Guardian