Unfortunately the source of this story is Intel, which is Arm's number one rival, but it might have some legs. Renee James told a company investor meeting that Microsoft will manufacture different versions of its upcoming “Windows 8” tailored for Intel and ARM-based devices. James is Intel's senior vice president and general manager of Intel’s Software and Services Group and he said that the next version of Windows for Intel chips will run programs designed for previous versions of the operating system, while the ARM-based versions will not. Intel plans to offer its own Windows-supporting architecture for mobile devices such as tablets.
Windows 8 will support SoC (system-on-a-chip) architecture, in particular ARM-based systems from partners such as Qualcomm, Nvidia and Texas Instruments. The big idea is that it would give Redmond the ability to port Windows 8 onto tablets and other mobile form factors powered by ARM offerings. This would allow Microsoft to push back into the tablet market.
But if an ARM-based Windows 8 can’t run legacy applications, it could stuff up adoption among those businesses and consumers. In fact there is the suggestion that Microsoft might do what it did to solve compatibility problems within Windows XP and Windows 7. Faced with that problem Microsoft ran the legacy software within a virtual environment. This would mean that Intel was telling the truth, but also that it was a bit wrong about how Microsoft would tackle it.