Bad to the Core?
Basically, a dual core processor is what the name implies: two physical processors and two memory caches on one piece of silicon. In theory, this will function like two separate processors. In order to take advantage of this, however, this real key is the software: the application must be able to send out multiple threads of data to each processor, similar in concept to the current Intel Hyperthreading. Very few applications (and no dental software) currently does this. However, dual core processors will show signicant improvements if you are running more than one application at a time, such as ripping a DVD and surfing the web at the same time. If you just run one program at a time, you won't see much benefit until software can take advantage of this.
Expect to see these first processors in the next month or so.