Besides looking a lot like Vista—and we mean a lot—Microsoft has said Windows 7 uses a lot of the same foundation, too, to keep upgrade migraines to a minimum. The problem is that its core ain't so suited to parallel computing, one of rival Snow Leopard's few headline features. So they're actually implementing some deep-level tweaks to bring it up to speed and make it more parallel processing friendly.
It's actually a significant process, since as Craig Mundie, Microsoft's Chief Research and Strategy Officer, admits, "Win32 was never designed for highly concurrent, asynchronous processing" and "parallelism requires adjustments at every level of the stack." The first steps toward the larger project of re-arranging tasks and runtimes in different layers to take advantage of multiple-core will happen in Windows 7 though, such as an updated scheduler. There will be other adjustments along these lines as well, though we probably won't know everything until October.
So while it's unlikely that Windows 7 be as deeply in tune with parallel processing as Snow Leopard looks to be, it'll definitely be able to use a SWAT team of cores better than your Vista box will, and set the stage for Windows 8 to have a solid parallel processing foundation. [ZD Net]