Microsoft Likely Revealing Windows 8 in September

Microsoft is holding a big event for developers in September, and will probably use it to show off the first public beta of Windows 8.

That means the OS will probably ship a year later, in fall 2012.

The new operating system is being tailored to run more effectively on tablet PCs -- for instance, it will run on the low-powered ARM processors used in tablets today, and will include new interface elements for touch screens.

That's critically important to keep consumers from defecting to non-Windows tablets, particularly Apple's iPad. Steve Ballmer has already called it the company's biggest risk ever.

Today at MIX, a conference for Web developers, Windows chief Steven Sinofsky said that the company would hold a Professional Developers'  Conference (PDC) from September 13 through 16 in Anaheim, California -- not in Seattle, as has previously been rumored.

Microsoft has not confirmed that it's showing Windows 8 at the event.

But the timing makes sense. Microsoft has  already started shipping test builds of Windows 8 to PC makers, and some screenshots have started to leak.

With Windows 7, Microsoft held a PDC in October 2008 and debuted the first public beta there. The final version shipped about a year later.

The company usually holds a big PDC only when a major new platform is debuting. In 2009, the company held one to promote the launch of Windows Azure, its cloud computing platform. Last year, Microsoft had a small event on its campus in Redmond, WA, with only 1,000 developers, and didn't show off any major new platforms there.

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