You knew that it was coming: the ramp-up to Windows 8.

Microsoft's kicking off what'll inevitably be a very long marketing campaign for its next operating system with the new "Building Windows 8" blog, complete with a first post by Steven Sinofsky, president of Microsoft's Windows and Windows Live division. What fascinating details does he reveal in those few hundred words?

Not that many, actually--although he devotes substantial amounts of digital ink to describing the philosophy behind Windows 8's radical user-interface changes, such as the abandonment of the "traditional" Windows desktop model in favor of colorful, Windows Phone-style tiles.

"So much has changed since Windows 95--the last time Windows was significantly overhauled--when the 'desktop' metaphor was established," he wrote in the inaugural Aug. 15 posting. "Today, more than two out of three PCs are mobile (laptops, netbooks, notebooks, tablets, slates, convertibles, etc.). Nearly every PC is capable of wireless connectivity."

Microsoft plans on revealing more about Windows 8 at its BUILD conference in September. "In the next weeks we will just start talking specifics of features, since there is no obvious place to start given the varying perspectives," he wrote. "From fundamentals, to user interface, to hardware support, and more, if something is important to you, we promise we'll get to it in some form or another."

Windows revenue declined a bit last quarter, largely due to softness in the overall PC industry, but Windows 8's presence on mobile devices could help take up that slack from traditional PCs. Still, coming so soon after the bestselling Windows 7 (and with Windows XP a dwindling but sizable presence on both consumer and enterprise PCs), will Windows 8 draw a substantial audience?

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