I have some queries:
Are the 68K and PPC not directly connected? It seems the PPC is a quite seperate entity. This means that it can't access the Amiga's chipset, surely? How are you communicating between the two CPUs? If you're using dual-ported RAM, how will you keep cache coherency?
It seems to me that this is a 68040 card with a PPC slapped on the side, which is great and impressive, but how do you actually use it? Is it like putting an SBC in a normal Amiga (i.e. a completely seperate computer which happens to be in the same tower)?
Without meaning any disrespect to the developers, given the complexity of the project, I'll believe it when I see it, and there's no way I'd pre-order one.... but I wish you all the best with it.