<Trolling>
Writing an OS for a processor family is nothing, compared to the needed writing for peripheral supports. So, as well as generic x86 support, what about GENERIC x86 compatible supports of hardware in the OS. Natively of course, NO PC BIOS. (there is no Bios on some embeded card, so you cannot rely on that). And able to support all the fancy graphics cards (dual headed and DVI included), as well as all the fancy sound card/extension/native... with full capabilities and optimal operations... Disk access is another story too. All I give you is hardware IRQ (possibly multiplexed and shared), and the full addressing range of the CPU. Oh, last point, the system CANNOT assign the IRQ, it is always a choice of value you have to support... good luck...
