IIRC, Hyperion (Actually, one of the Freiden's I think) said in theory you would need 8mb Run OS4.0. Thats not taken into account 68k JIT emulation, which I understand would need more. I reckon you might get away with 32mb.
I also read that the order would be:
Cyberstorm PPC
AmigaOne
Blizzard PPC (hopefully)
This was all from the AmigaOS4 mailing list. And is subject to my memory not being corrupt!
J
