On sale for less than a week, Microsoft's latest software offering, Windows 8, has sold more than four million upgrade copies alone, according to Microsoft chief executive Steve Ballmer speaking at the BUILD conference in Seattle.
Only today, in an interview with The Wall Street Journal, Ballmer was not willing to disclose anything on the record about how well the latest operating system was selling. However, the software giant threw open the doors on at least one key metric.
Microsoft has also shopped "tens of millions" of Windows 8 to its partners around the world, according to Ballmer. The chief executive added that enthusiasm is "very high" for the next-generation operating system.
He also said the Seattle, WA.-based company is also seeing strong interest from business and enterprise users, and that Windows 8 was even outselling the software's predecessor, Windows 7, during the same period after launch in July 2009.
By comparison, in the same four days after Apple released the latest iteration of OS X, dubbed "Mountain Lion," the Cupertino, CA.-based technology supergiant reported that more than 3 million copies of the software had been downloaded from the Mac App Store.
However, Ballmer remained quiet on dishing out any specific figures relating to the Surface RT tablet, which went on sale on October 26 to coincide with the Windows 8 launch.
While many U.S. buyers of the Surface RT tablet received their devices on the day of launch as promised by Microsoft, most European buyers are still waiting for their tablets to arrive, four days after delivery should have begun, according to ZDNet crowdsourced research.