> I believe they're quite similar clock for clock.

Okay, so accordingly G4 above 1.2 GHz should still be faster than current Cortex-A9.

> A9s tend to have bigger caches and faster memory than the G4s ever had.

Faster memory bus yes, but bigger caches than G4s ever had? While the core is specified by ARM for up to 4 MiB L2 cache I couldn't find any actually existing Cortex-A9 with more than 1 MiB L2 cache. MPC7448 has 1 MiB L2 as well. MPC745x has less L2 but can have L3, e.g. MPC7457 has 512 KiB L2 and up to 2 MiB L3.

> I meant the lower range of the G5s

That's what I referred to with "1.6 GHz G5 (the slowest of the bunch)" as that is the very bottom of the G5 range. I still doubt that a 1.8 GHz Cortex-A9 would beat it.

> remember the G4 was faster per clock than the G5.

I don't think that's generally true except for AltiVec/VMX code.

> what I meant was the Qualcomm chip at 2.5GHz.

Ah okay, so that was a misunderstanding from my side, sorry. A 2.5 GHz Krait could possibly beat a 2.5 to 2.7 GHz G5, yes.

> It's sampling now so should be a year (or less) away.

I'm not sure Krait based chips are really sampling at 2.5 GHz already. Some sources say the MSM8960 will only clock up to 1.2 GHz and it will take until the APQ8064 to actually reach 2.5 GHz:

http://www.electronista.com/articles/11/06/02/qualcomm.dual..and.quad.core.processors.inbound/

> It looks like Nvidia's "Project Denver" should blow any G5 clean into next week.

Sure but that's even further away than Cortex-A15.