> [...] or a fork, with team MorphOS supporting any new PPC hardware
> that becomes available

A1222/Tabor will remain unsupported either way, I guess ;-)

> if (or when) MorphOS comes to x86 will it be easier/faster to port
> open source software which exists for Windows/Linux for the same CPU?

Yes, it would. Existing ASM and SIMD optimizations could be used directly, and source-code dependency on little endian byte order wouldn't be a problem.