Microsoft's innovative "Courier" tablet prototype--which, if produced, would have offered two touch-screens bonded together in a book-style format--now has a cause of death: crushed with extreme prejudice by Windows 8.

According to CNET's Jay Greene, who interviewed a number of unnamed executives with knowledge of the company's tablet deliberations, Microsoft CEO Steve Ballmer had a choice to make: either support Courier, which executive J Allard (famous for helping conceive and push the Xbox) touted as a complementary device to PCs and smartphones, or wait until Windows and Windows Live division President Steven Sinofsky could build a version of Windows capable of running on tablets. The latter would take substantial time.

Ballmer went to former Microsoft CEO Bill Gates, who in turn focused his laser intellect on the dilemma. And Gates had one big issue with Courier: namely, it wasn't intended to run Exchange or Outlook, instead pulling down email via the browser. "The device wasn't intended to be a computer replacement," Greene wrote. "The key to Courier, Allard's team argued, was its focus on content creation."

Gates, according to an unnamed Courier worker quoted in the article, had an "allergic reaction" to the concept. After all, Microsoft has grown on the concept of supplying an integrated ecosystem of software products, portable across a wide variety of form factors. Something that operates outside that matrix, well, is an outlier.

Within weeks, according to Greene's sources, "Courier was cancelled because the product didn't clearly align with the company's Windows and Office franchises."

Microsoft has now placed all its tablet chips on Windows 8. The operating system, due for arrival sometime in 2012, offers a Start screen loaded with colorful tiles linked to applications, and meant to operate equally well with traditional PCs and touch-centric devices. It also allows users to switch to a "regular" desktop interface.

Tablet interoperability will place Windows 8 in a head-on vector with Apple's iPad, which currently dominates the tablet space. Other touch-screen competitors, including a variety of Google Android tablets and Hewlett-Packard's TouchPad, have crashed and burned in their attempts to seize their own portion of the tablet market. That's either a portent or an opening for Microsoft, depending on how you look at it; certainly the company intends Windows 8 to offer a robust "no compromises" experience on tablets, which could boost its appeal with the same business users who already constitute a significant portion of Microsoft's core audience.

All that being said, I can't help but feel a little twinge of sadness over Courier's premature death. It was a cool concept, even if it never saw the light of day.

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