“We’ve had a great response here in Japan,” Ballmer said. “Certainly we’ve seen initial sales be fantastic. The first ten days were bigger than the first ten days of XP or Vista or any other Windows launch that we have done.”

And indeed that would seem to be the case. According to research outfit NPD, Microsoft (MSFT) sales of Windows 7 in its first few days on the market were more than triple Vista sales for the same length of time.

With those words, spoken at a big company event in New York City (see video below), the Microsoft CEO launched the newest version of Windows, the one he hopes will regain the customer goodwill lost with its predecessor, Vista. There’s no question that the stakes are particularly high this time around. Vista was widely maligned as mediocre, and Microsoft (MSFT) needs something to reverse three quarters of declining Windows sales.

By most accounts, Windows 7 fits that bill. Reviews of the new operating system have been largely positive, calling it faster, more secure and easier to use that its predecessors. Our own Walt Mossberg describes it as “the best version of Windows Microsoft has produced…a boost to productivity and a pleasure to use.” Quite an endorsement, but one that was hard won. According to Microsoft, more than eight million people participated in the Windows 7 beta program–more than for any Microsoft beta program ever.

In any event, if any OS has a shot at succeeding Windows XP as the world’s most ubiquitous operating system, it’s Windows 7. “I think Windows 7 will be the biggest, one of the biggest, products to hit the tech industry this year,” Ballmer told CNBC. “Just because Windows is used on about one billion computers around the planet. There’ll be another 300 million machines that ship this year, and the diversity of PCs that ship with Windows 7, the simplicity that Windows 7 brings–I think it’s a pretty banner year.”

“The launch of Windows 7 has exceeded everyone’s expectations, storming ahead of Harry Potter and the Deathly Hallows as the biggest grossing pre-order product of all time at Amazon.co.uk,” Amazon’s Brian McBride told the Telegraph. “Demand is still going strong. Over the past three months, only Dan Brown’s The Lost Symbol has sold more copies than Windows 7, which is an incredible achievement for a software product.”

And an incredible achievement for Microsoft (MSFT), especially after that monument to disappointment, Windows Vista. Seems those early discounts and launch parties paid off. Well, maybe not the launch parties.

Those ruthless, conniving bastards. Strategizing to thwart a rival.

I’m sure nothing of this sort goes on over at Google (GOOG), where everything is altruism and Segways and don’t-be-evil happy rainbows. Surely, the lobbyists Google employs are working exclusively to advance the company’s mission of organizing the world’s information and making it universally accessible and useful. They’d never do anything untoward like conspire to protect Google’s interests from a competitor. They’d never, for example, draft an antitrust complaint to the Justice Department that forced Microsoft (MSFT) to make changes to its new Vista operating system.

Please. This is business is usual. And if Google’s lobbyists aren’t holding a weekly “Screw Microsoft” meeting or some variation on that, then Google should get some new lobbyists.

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.

Why the hesitation? A little gun-shy after that ill-starred Vista deployment? Perhaps. Of those surveyed, 42 percent cited lack of time and resources as their reason for not upgrading. 39 percent said they had concern about the compatibility of Windows 7 with existing applications (click on chart below).

Always wise to wait for the release of that first service pack, right? That said, the fact that nearly 40 percent of businesses do plan to upgrade by the end of 2010 is noteworthy. That’s a high level of adoption for a new OS, especially in the current economic climate.

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.

Said Microsoft: “Windows 7 Professional and Ultimate customers will have the option to downgrade to Windows XP Professional from PCs that ship within 18 months following the general availability of Windows 7 or until the release of a Windows 7 service pack, whichever is sooner, and if a service pack is developed.”

This means OEMs could still be selling XP-equipped PCs as late as April 2011. Which is astonishing when you recall that the company originally planned to cut off sales of XP on Jan. 30, 2008, one year after Windows Vista debuted. But the poor reception given Vista and the unwavering loyalty of XP users caused the company to extend that deadline to June 30, 2008. A few months later, Microsoft (MSFT) pushed the deadline out further, to Jan. 31, 2009. Then, amid reports that more than a third of all new Vista PCs were being downgraded to XP, Redmond extended the XP deadline to May 30, 2009. The company subsequently pushed that extension out to April 22, 2010.

And now we’re into mid-2011.

Slick. The trackpad now feature Chinese character support. Users simply draw the characters with their fingers.

Check out our WWDC 2009 Full-Coverage special feature for more WWDC news.

Though Windows 7 is expected at market by the end of the year, the United States military has set that as a deadline for its migration from Windows XP to the “worthy, but largely unexciting” Windows Vista and from Office 2003 to Office 2007.

The Army has been testing Vista since 2006 and its decision to move forward with a migration of its 744,000 desktops–on both classified and unclassified networks–was apparently driven by the OS’s improved security. “First, they see real value in Windows Vista’s improved security architecture,” Microsoft senior director Gavriella Schuster said in a statement. “Second, it shows large organizations have unique needs and timetables for deployment. These things take time–they have been rigorously testing internally–and it makes sense that they have approached deployment in a measured and well-planned way, especially given the number of seats they are migrating to Windows Vista.”