I'm pretty sure this topic will have already been done to death if you search around, but basically due to a lot of applications not yet being optimised (Universal Binary) to run on Intel chips the answer is no - the Intel Macs aren't as much faster at everything as we are led to believe. You need not run out and buy a MacBook just because.
However, the Intel chips are the future, and as more and more applications become Universal Binary there will be greater and greater performance gains - not to mention the other advantages that Intel chips will bring, such as chips more suited to low heat and power environments that could possibly spawn a whole range of new and exciting products.
Enjoy your Mac 🙂