Microsoft is not planning to offer a version of Windows for upcoming ARM-based smartbook products.

Smartbooks are a relatively new form factor - small, ultraportable devices half way between a smartphone and a netbook. Most will be based on ARM chips from TI, Freescale and Qualcomm, which means they can't run x86 operating systems such as XP or Vista. They can use Windows CE, but this is barely a substitute for proper desktop OS.

Steve Guggenheimer, head of Microsoft's OEM division claims Redmond will not develop a new version of Windows for ARM-based devices. He was also pesimistic about smartbooks in general, saying it's hard to create new product categories.

This basically means ARM smartbook vendors will be forced to offer devices with Android or Linux, while some might even opt for Windows CE. Products based on Nvidia's Tegra chips will also face similar difficulties.

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