http://hothardware.com/News/Microsoft-To-Unveil-Windows-9-Threshold-This-Tuesday-930/
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It feels like just yesterday that we were investigating the ins and outs of Windows 8, and already, enough time has passed that a new version of Microsoft's flagship desktop/laptop operating system is imminent. Windows 9, code-named Threshold, may end up dropping the number on its end altogether. At this point, Windows itself is a pretty powerful brand, and some analysts think that Microsoft may allow it to stand on its own when it's released to the public "early next year."
The name change also highlights Microsoft's acceptance of the fact that we're truly living in a post-PC world. As mobile and computing fuses together, we're likely to see the "Phone" dropped from "Windows Phone" and the numbers dropped from "Windows." It's quite possible that one Windows could be built to serve all of Microsoft's various platforms, using the lessons from its Windows RT misstep as guidance.