Back in December, a rumor emerged that Microsoft could be ditching the traditional Windows desktop for Windows 8 ARM tablets, signaling a move towards the Metro style user interface as the sole ARM strategy. Microsoft has consistently refused to comment on its plans for Windows 8 ARM, and has been reluctant to let vendors show off tablets running on ARM chipsets. The air of secrecy has created uncertainty for application developers and confusion for analysts and media who follow the company's every move. So what happens if Microsoft isn't removing the desktop, it's just restricting it? That's exactly what we are hearing the software giant plans to do.

Microsoft is said to be contemplating a restricted desktop for Windows 8 ARM involving trusted certificates for ARM desktop applications. ARM tablets running Windows 8 are designed to be Microsoft's alternative to Apple's iPad, and the company is keen to ensure applications do not affect the battery life. Microsoft's Windows 8 Metro style work involves a number of measures to suspend applications cleanly, something not available for legacy applications. Desktop applications on Windows 8 ARM will likely be restricted to just Internet Explorer and Office, and we're hearing the Office team has put a lot of effort into Office 15 to ensure it is power efficient for ARM devices.

Microsoft demonstrated its early Office work on ARM chipsets last year, and the company's Windows planning and hardware chief Michael Angiulo, made it clear that "ARM isn't just for tablets," leaving it up to system builders to decide "what the next generation of PCs look like" while they "all have control of the Windows desktop." Don't expect to see ARM laptops and convertibles straight away though, Nvidia CEO Jen-Hsun Huang believes tablets will come first. We understand that Microsoft won't deviate from its desktop on ARM plan, but that any developers wishing to build ARM desktop apps might have a tricky time getting a signed certificate from the company.

A Windows 8 beta, labeled as a "Consumer Preview," is due in the coming weeks, and one source has revealed Microsoft is building escrow copies of the software — a phase prior to the final sign-off on a significant Windows milestone. The latest, build 8220.0.120127-1925, is said to be the initial work towards a final beta copy. Whether or not Microsoft has made a final ARM strategy decision by beta remains to be seen, but developers are eager to hear about the possibility of full desktop apps on Windows 8 ARM and could be left frustrated by restrictions.