Making RISC OS work natively on IA-32 would be a huge undertaking. So much of RISC OS would have to be rewritten that it'd only half be RISC OS anymore. It's doubtful there'll ever be a standalone edition of VRPC that boots itself, as turning an application into an operating system would be a major chore with drivers and bootloaders to consider.
That being said, I'm sure RISC OS would end up being ported to x86 if it was open sourced. I doubt that'd happen until RISC OS truly becomes worth nothing from a business point of view. Maybe in ten years.