Are i5's and i7's really much faster? The clock-speeds are basically the same. I know there's more to it, like cache size and such, but clockspeed and number of

Are i5's and i7's really much faster? The clock-speeds are basically the same. I know there's more to it, like cache size and such, but clockspeed and number of cores is a lot of it, and that only changed slightly. (2.33GHz->2.4GHz for the cheap 15", I believe.)