According to Macworld's just published test results comparing low end Mac Pro to the high end iMac:
Been waiting to see some benchmarks on the 24" iMacs.You would expect an iMac powered by the fastest Core 2 Duo chip available to outperform iMacs with lesser clock speeds. And that was certainly the case when we ran our benchmark testing on Apples build-to-order iMac Core 2 Duo with a 2.33GHz processorit easily beat its fellow Core 2 Duo models as well as an older Intel-based iMac running on a 2GHz Core Duo chip.
But what you might not expect is for that high-end consumer machine to beat out a professional tower powered by two dual-core chips in Macworld Lab tests. Nevertheless, thats exactly what happenedthe 2.33GHz iMac Core 2 Duo edged past the 2GHz Mac Pro.