I'm sorry, but I don't see remotely the same momentum happening on the PPC platform.
Of course you don't see it, it isn't happening at the moment. And I'm not saying it
will, either - I'm just saying, don't rule out the possibility. The architecture is still around and has been gaining traction in the console market since the release of the PS2 (going from one console to
total market dominance in the space of a single generation.) It may make a comeback or it may not, but I think it's still within the realm of possibility. ARM is the Next Big Thing at the moment, but so was multi-core x86 before it, and back in the mists of time (a.k.a. the mid-'90s,) so was PPC. Things change, often in ways you wouldn't expect.