I think that by now Intel should have already broken the 3.0 GHz barrier. I mean, the last processors to reach those speeds were the Pentium 4's which almost reached 4 GHz.
Intel should really look into faster CPUs now that the FSB bottleneck is over in the new Nehalem architecture. I mean, its almost 2010 and we are still playing with 2.0 GHz CPUs? What the hell, we should have 2.8 GHz as a minimum now a days.
The GHz wars died with the Pentium 4. The clock speed is not the issue, the performance is, hence the AMD athalon chips could waste the P4's at a much lower clock speed. Intel adapted, abandoned its ambition for that elusive 4 GHz mark, and went toward the Core architecture.
And 4 GHz has been reached quite easily on the the Core 2 Duo chips with a straightforward overclock (no liquid nitrogen).
This transition away from very fast single threading is going to make way for slower, but much more efficient and productive, massive multi-threading. hence Nvidia pairing its 9400 gpu with the intel atom as a first step.
i am sure you know this, just reference for other readers