I have bad feelings about adapting a G4 board for use with the new PPC970, it is not a bus question but a more complex question: there is a range of things to fix in order to achieve the expected performance level from these CPUs and Apple know this well.
According to one of their Tech-notes
(
http://developer.apple.com/technotes/tn/tn2087.html)
the list of DOs and DONTs is quite long and involves even such common things like type conversion, cache access, ...
Oh, I was forgotting the best: the 970 lacks some cache control instructions the G4 implements, so the cache section of the AmigaOS 4 would have to be rewritten anyway!
Bye,
Claudio
