There has been quite some noise around the talk that Eric Traut (Distinguished Engineer) give at the University of Illinois. During his talk Eric showed something is called MinWin which is a stripped kernel of Windows 7 that will be the basis of our future products. Not just the Windows OS but it's also the OS used for media centers, for servers, for small embedded devices . However MinWin is internal-only and won’t be productized as such.
MinWin is 25 MB on disk; Vista is 4 GB, Traut said. The MinWin kernel does not include a graphics subsystem in its current build, but does incorporate a very simple HTTP server. The MinWin core is 100 files total, while all of Windows is 5,000 files in size. This is something big, the kernel is so small that there is no graphical subsystem, in the screenshot below you see that when booting the Logo is build from ASCII characters. Pretty cool.
Further Eric also explains that in the Windows Server Virtualization technology we expose Hypercall's which can be compared to kernel calls and earlier this week we announced that those Hypercall API's will be available via Open Specification Promise. Read more about that at the Windows Virtualization Team Blog
I encourage you to watch the full video of Eric Traut’s talk ,because he explains our Virtualization technology more in depth.