system-on-a-chip architectures using ARM processors. Unlike the x86 architecture that today's Windows laptops and desktops work with, ARM-based chips tend to run such low-power devices as tablets and smartphones.
In his CES keynote speech, Microsoft CEO Steve Ballmer said, "This announcement is really all about enabling a new class of hardware, and new silicon partners for Windows, to bring the widest possible range of form factors to the market."
In other words, Windows won't be just for laptops and desktops anymore.
Microsoft's ARM announcement represents the firm's only officially released factual detail about Windows 8. Consistent with it, the company named Nvidia, Qualcomm, and Texas Instruments as silicon partners, so Windows devices built upon their three low-power platforms are likely.
At an architectural summit in London last year, Microsoft encouraged the idea of virtualising Windows more heavily, possibly storing apps, data, Windows settings, and parts of the OS itself in the cloud.
No rumour about Windows 8 is more precise than a series of leaked slides that supposedly provide a blueprint for Microsoft's next OS. The slides alone don't indicate final features of Windows 8, but they do show where Microsoft is headed, especially since other reports have corroborated them.
One slide, for example, talks about an OS that follows users wherever they go; instead of being tethered to hardware, users may roam between desktops, laptops, and tablets in whatever way is most convenient.
Another slide speaks of a reset button that preserves apps and settings while wiping out viruses and other hindrances. Some industry watchers suggest that storing apps and data in the cloud could make this feature possible.
As for Microsoft's goal of "instant on" computing, blogger Manan Kakkar spotted a Microsoft patent for using a hypervisor-another virtualisation method-to split the operating system into a general-purpose OS and a number of appliance-like applications, such as for TVs and tablets. Those uses, Kakkar says, could switch on instantly even if the core OS took 30 seconds to start up.
How will Microsoft achieve these lightweight versions of its operating system? A rumour circulated by Paul Thurrott posits that Windows 8 will introduce a tile-based interface called "Mosh" to serve as an alternative UI for tablets and other low-power touchscreen devices.
We've also heard rumblings about a new application development framework code-named "Jupiter," whose goal is to help developers create dynamic, visually appealing, and immersive applications for a forthcoming Windows app store. It may also be an attempt by Microsoft to enable developers to create apps that work on both traditional x86-based CPUs and ARM-based processors without extensive recompiling and reprogramming.
If you doubt whether Windows 8 will be a profoundly different operating system from its predecessors, consider this breathless bit of hype that briefly appeared on a Microsoft developer's blog in 2009:
"The minimum that folks can take for granted is that the next version will be something completely different from what folks usually expect of Windows...The themes that have been floated truly reflect what people have been looking [for] for years and it will change the way people think about PCs and the way they use them. It is the future of PCs."
Microsoft quickly removed the blog, as if to erase the evidence. So is the company really trying to shake things up with Windows 8?
The Big Picture
Microsoft clearly wants to create an operating system that scales between devices. ARM support provides the foundation, and cloud services could be a major building block. The challenge for Microsoft will be to leave the core Windows experience and legacy compatibility intact while also pursuing its lofty ambitions.
A final rumor: Reportedly, Microsoft is targeting a 2012 release for Windows 8. Think the company can get everything figured out by then?