Based on Apple's benchmarks, I think it's safe to approximate the 2x2.93 GHz Nehalem Mac Pro to be about 1.3x the speed of the 2x3.2GHx Harpertown for well-multithreaded applications that utilize all the multi-core performance available. I think it's also safe to assume that performance between different speeds of the same family of processors can be approximated as being linear, eg. twice the clock speed is twice the performance. So, let's do the numbers (considering only CPU performance, not GPU-accelerated processes)... Using a 2x2.8 GHz Harpertown as the baseline (since it was the best performance value available in the previous generation, pricing source from EveryMac), but adding US$137.95 for 4GB RAM to get its memory equal to the Nehalem models (the Harpertowns came with only 2GB RAM): 2x2.8H (US$2937): 1x performance, 1x price, 1x performance/price 2x3.0H (US$3737): 1.07x performance, 1.27x price, 0.84x performance/price 2x3.2H (US$4537): 1.14x performance, 1.54x price, 0.74x performance/price (relative to original price 2.8 GHz Harpertown Mac Pro upgraded to 6GB RAM from OWC) Since Apple's benchmarks compare the two most expensive variants of the current and previous generations, the conversion goes like this: 1.3*(Nehalem speed/2.93)*(3.2/2.8) 2x2.26N (US$3299): 1.15x performance, 1.12x price, 1.03x performance/price 2x2.66N (US$4699): 1.35x performance, 1.60x price, 0.84x performance/price 2x2.93N (US$5899): 1.49x performance, 2.00x price, 0.75x performance/price (relative to original price 2.8 GHz Harpertown Mac Pro upgraded to 6GB RAM from OWC) Remarkably similar to the previous generation. With the base model, provided you make use of well-multithreaded applications, you're getting the performance of the previous 3.2 GHz machine without the performance/price penalty that the original 3.2 upgrade had. So, why is this update causing such a dissatisfied stir? Well, because performance/price did not improve much at all, which is contrary to expectations of updated technology. For comparison, when the 2x2.8 GHz Harpertown came out, it was approximately 1.8x as fast as its 2xDual-core 2.66GHz predecessor (and that's being generous) for 1.12x the price, or a 1.6x performance/price improvement. That's what's missing with the Nehalems. Furthermore, if you can snag a 2x2.8 GHz Harpertown for nearly any discount, you're coming out ahead for your money, as long as you're satisfied with a little less absolute speed. That's some great technological progress, huh? Independent benchmarks should clarify this further. Thoughts?