In May 2007, Bill Gates revealed that his company had sold 40 million Windows Vista licenses. During his final keynote in January 2008, Gates announced that Vista sales had crossed the 100 million threshold. In April 2008, the company revealed that Windows Vista had sold over 140 million copies. Three months on, in its fourth quarter earnings report, Microsoft is claiming that another 40 million licenses have been sold (the increase is probably due to the release of SP1):

Revenue growth was primarily driven by continued customer demand for all products, including Windows Vista, which has sold over 180 million licenses since launch, the 2007 Microsoft Office system, server software, and Xbox 360 consoles and games.

The 180 million number came along with the company's announcement that it had hit an annual revenue mark of $60 billion. Vista has been available for over 18 months, so an average of 10 million licenses sold per month is quite impressive. Microsoft is, however, counting sales and not users; some customers have decided to downgrade from Vista back to XP (they can upgrade to Vista as they please) but these are still counted in the sales numbers. Estimates state that it took 51 months for Windows XP to reach 400 million users, but neither XP numbers nor Vista numbers take into consideration the millions of copies of Windows that are pirated.

Microsoft rarely gives out sales numbers, but Vista is another story. Due to bad press, the company apparently wants to remind everyone that Vista is still selling well. The software giant recently announced that it would be putting resources into launching a marketing campaign that will fight back against Apple's ads and incorrect Vista assumptions and will instead tell the "real Vista story."

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