PPC was a logical way to go due to it being Motorola processors and claimed to be rather compatible with the 68k series (or at least, it would be easy to emulate).
The reason the PPC no longer is available is that PhaseV rolled over and died (only to re-incarnate as bPlan ;-)). Sure, DCE had a go at it but by then, the Amiga market was already really really small. Eyetech had encountered that as well, resulting in a not enough sold / produced Amiga-ones.