>>> it just occured to me, that binaries with FPU code, will not be able to run on the e500
>>> cores without some kind of real-time FPU code translation, with performance loss.

>> Exactly, though only true for e500v2 (and before), which the P1 (and P2) series has.

> I just realized that for backwards compatibility, perhaps P1022 is not the best case,
> though attractive overall. It would need some serious work on the FPU real-time
> translation, and I can't even estimate the impact of that.

It seems this didn't hold back some people from working on a combined m68k/PPC expansion board for the Amiga 3000 and 4000, using the single-core version of the QorIQ P1022, which is the P1013, as its 1.0 GHz PPC CPU:

http://www.ultimateppc.nl

Close-up of the prototype board shows the QorIQ P1013 at 800 MHz:
http://www.ultimateppc.nl/img/uppc_reva_devboard_g2_20120507.jpg

As you said, a Power Architecture CPU with an e500v2 core isn't likely to be a good choice for hardware that's wished to provide backwards compatibility with WarpOS/PowerUP binaries or even compatibility with MorphOS or OS4.

Statements with respect to this taken from http://www.ultimateppc.nl/faq.php :

"Q: Will the PowerPC run AmigaOS4.x / MorphOS / etc. ?
A: We hope so! We will work actively with any developer to get these OSes supported on the UltimatePPC.

Q: Will the PowerPC CPU be supported in WarpUP / PowerUp under the Classic 3.x OS versions?
A: That would be awesome. It will be a very difficult task because for this to work as we would need to have a compatible kernel that runs on the UltimatePPC. The PowerUp / WarpUP kernel is closed source and not available to us and we would need to work around the slight differences in architecture. We would love to see this If you have voodoo coding skills, know how and want to put in serious effort please let us know."