The performance of a processor is defined more than by just the listed clock speed. For example, the amount of cache, which is what differentiated the the pentiums from the celerons back in the day. The supposed new processor in the iPhone 3GS has a different architecture that improves its overall performance by something like 1.5-2X.
The perfomance of the new iPhone is most likely due to increased Ram and a more powerful processor. Nothing is confirmed, but I'm 99% sure this is what is causing the performance boost.
Exactly what I'm saying. I just don't think a 200 mhz clock increase on the current processor with no change in RAM would cause that noticeable of a performance increase.
We'll wait for iSuppli I guess!