And by many accounts, Windows 7 is poised to do just that. Unlike Vista, it was completed on time. And unlike Vista, early reviews have been positive.

“Even in beta form, with some features incomplete or imperfect, Windows 7 is, in my view, much better than Vista, whose sluggishness, annoying nag screens, and incompatibilities have caused many users to shun it,” Walt Mossberg said of the OS back in January. “It’s also a serious competitor, in features and ease of use, for Apple’s current Leopard operating system.”

So Microsoft (MSFT) has good reason to be proud of this release-to-manufacturing, or RTM, milestone. There’s a lot riding on Windows. And the company seems to be very much on point as it brings the newest version to market.

“Today’s release is the result of hard work and collaboration with our partners in the industry to make Windows 7 a success,” wrote Microsoft’s Brandon LeBlanc in a post to the Windows 7 Team Blog. “We delivered Windows 7 with a predictable feature set on a predictable timetable that allowed OEMs [original equipment manufacturers] to focus on value and differentiation for their customers. We continue to be overwhelmed at the community’s response to Windows 7 and it has been an extremely rewarding experience to witness. We hope the enthusiasm will continue to grow even more as our partners build amazing experiences with their products and Windows 7.”

Ironically, this particular build of Windows 7–Build 7600.16385–which Microsoft designated as RTM, was leaked to the Internet nearly a week ago and has been available for download via BitTorrent ever since.

And so the company today said that beginning Friday, “select markets” can preorder Windows 7 at a more than 50 percent discount. In the U.S., that means Windows 7 Home Premium will set you back about $50, or Windows 7 Professional about $100. A “screaming deal,” Microsoft calls it.

The promotion runs until July 11 in the U.S. and Canada and until July 5 in Japan, or “while supplies last.” If you choose not to preorder an upgrade copy, you’ll obviously pay a bit more for Windows 7 when it finally ships on Oct. 22. Existing XP and Vista customers in the U.S. will be able to purchase Home Premium for $119.99, Professional for $199.99 and Ultimate for $219.99. New customers will pay $199.99 for Home Premium, $299.99 for Professional and $319.99 for Ultimate.

Pricey, but about 8 to 17 percent less than Vista. Said Brandon LeBlanc, Microsoft’s in-house Windows blogger, “Overall, customers will be paying less and getting more with Windows 7.”

For their sake, let’s hope so. Especially if they paid retail for Vista.