A new Microsoft patent application, titled "FAST BOOTING A COMPUTING DEVICE TO A SPECIALIZED EXPERIENCE" took the idea of "instant-on" solutions to the next level with a hypervisor-enabled fast-boot dual-boot solution that makes much more sense.
The patent app outlines a boot process involving a general operating system like Windows alongside many special purpose operating systems that boots much more quickly to provide "appliance-like behavior" such as viewing entertainment content (TV, music, DVD).
Manan Kakkar suggest that this feature may even be a part of Windows 8 as "Direct experience":
With Windows 8 now on SoC, I see television sets installed with Windows configured to boot into media center to play your music, DVDs or movies. Google TV competitor and Windows everywhere? It's on. Congratulations on your 11 years as CEO, Steve B. This also fits well with the rumors about more than one UI with Windows 8. It complements my theory of having distinction between general purpose OS and more mobile/media focused OS, tying it all together quite well.
The patent further explains how drivers for specific devices will be shared by the General Purpose and Specific Purpose OS instances.
Here's the abstract:
Described is a technology by which independent computing functions such as corresponding to separate operating systems may be partitioned into coexisting partitions. A virtual machine manager, or hypervisor, manages the input and output of each partition to operate computer system hardware. One partition may correspond to a special purpose operating system that quickly boots, such as to provide appliance-like behavior, while another partition may correspond to a general purpose operating system that may load while the special purpose operating system is already running. The computer system that contains the partitions may transition functionality and devices from one operating system to the other. The virtual machine manager controls which computer hardware devices are capable of being utilized by which partition at any given time, and may also facilitate inter-partition communication.