sa110: But whilst RISC OS relies on ARM it'll inevitably stuck with slower and more expensive hardware than other platforms. I really wish I was wrong there, but I can't see ARM wanting to change direction (unless someone tries to design a completely integrated system, from mobile phone to desktop machine, all running the same OS and software. I dream on).
A move to x86 would probably bring in a huge number of new and returning users, and something like VRPC could be used for legacy stuff (including parts of the OS, no doubt). If it did get the numbers then whatever fork it's on would quickly become the main one. OTOH if I'm wrong about it bringing in users then the whole exercise would be a monumental waste of time and effort, if it's even techincally feasible in the first place.