> I know that FSB speeds are irrelevant now more than ever with multithreading and multi-core architectures

Clock speeds have been irrelevant ever since there has been more than one architecture for the same instruction set. You cannot compare a 3GHz i7 with a 3GHz Pentium 4 of equal core count and say that, just because the clock is ticking at the same speed, Intel isn't doing enough to improve performance. There would be a vast effective difference in just about every kind of workload, just due to architecture improvements.