Apple moving their platform from PowerPC to Intel does not mean that OSX will be running on your PC machine (i.e. the same one you could run Windows on).
It will likely be just as proprietary hardware as Mac hardware is today, but powered by future (not invented yet) Intel x86_64 processors that run cooler than today's Pentium M processor line.
Of course within hours, this same hardware will be running Linux, and through Rosetta (or Universal Binaries), will be running Microsoft Windows applications, but don't expect to simply buy OSX for x86 to "dual boot" on your PC anytime soon. OpenFirmware is quite non-PC-like, and not likely to be found on any clone motherboard, so thats a blocker.
Its going to be an interesting few years, but its just proving what I said publically on a couple of mailing lists about 6 years ago...
"We'll all be running multiple operating systems on the same hardware at the same time... and we won't care. Your applications will 'Just Work' and you won't have to worry about them crashing."
With virtualization software becoming near real-time production quality and processor speeds getting fast enough to close the gap between emulation and "real", it makes sense to start building virtualization hooks into the raw silicon itself. Put a JIT for runtime application/endian translation into the silicon and run a minor translation layer at the application level, and you've pretty much solved the problem of OS-specific applications and binaries.
This is where we're heading... the OS will become anonymous and you won't need to know, or care, what the underlying OS is, just as long as your applications continue to function.