Intel used the philosophy of shrinking the size of the while ramping up clock speeds as much as possible. This approach has lead to overheating and a problem called silicon leakage has forced Intel to redraw their strategy into multi core processors which combines 2 execution cores into a single piece of silicon which will boost the ability to multitask. The big issue is will the duo core provide a performance boost without comprimising battery life. Because of the hyper-threading on the P4 the software industry was got a head start and you will see a big influx of software that takes advantage of using multiple treads once MS Vista in released. Intel also plays to have Quad Core processors in the next 2 years.