I'd say no. MorphOS Team has said on several occasions that they won't port to 'custom hardware' ever again (presumably if not paid an appropriate sum for the port, that is).
> There is so much easily and cheap obtainable fast hardware
There will be the day when PPC Macs won't draw anyone from the woodwork anymore in terms of performance. In 5 years from now the last PPC Mac will be one decade old. So I think it's justified to think about what could come after PowerMac G5.