IBM's future Power and PowerPC plans
ThinkSecret has an article
about IBM's future plans for the POWER processors. Current PowerPC processors at IBM (970, 970FX, 970GX, 970MP) are based on the POWER 4 line of processors (basically, they're scaled down and include AltiVec).
It's currently unknown, however, whether future versions of the PowerPC will be direct derivates of POWER 5 or 6 - or rather an evolution of the PowerPC 970 line of processors. Yet another processor, the Cell processor, could also have an impact on processors made by IBM and used by Apple. The nearer future however seems a bit clearer. Apple can soon get its hands on the 970GX and 970MP. The GX chip would make sense in iMacs and eMacs, the MP for PowerMacs. None of those chips is really intended for use in notebooks, however.