This is also true of Windows 7 editions, with the premium versions having more features and functionality than the basic versions. However, Microsoft said it plans to remove some disparities between the different SKUs of Windows 7 by making them all a "superset of one another," so if people decide they want to upgrade from, for example, Home Premium to Professional, they won't lose any functionality from their previous version in that transition, it said.

"With Windows 7 there is a more natural progression from one edition to the next," Microsoft said.

Microsoft has targeted late this year or early next year for the release of Windows 7. The OS is currently in its first public beta, but Microsoft said last week there would be no beta 2, as there typically is with its software products. Instead, the next release of Windows 7 will be a nearly completed release candidate.