Microsoft, which unveiled the Xbox 360 in May, had already announced plans to launch the console this year in the United States ahead of the holiday season, which begins in late November.
The software giant had previously said Japanese and European launches would follow within six weeks.
Microsoft's new white-and-silver concave console will feature three PowerPC-based microprocessors joined onto one chip to deliver powerful computing and advanced graphics, as well as a detachable 20GB hard drive and a wireless controller.
The software giant aims to unseat game market leader Sony by launching the Xbox 360 ahead of Sony's planned launch of its PlayStation 3 in spring 2006.
Sony controls more than two-thirds of the game console market.