Apple has been doing innovative designs for a long time now, they know what they are doing. I'm sure they wouldn't put out a design that would just die under normal conditions, the QA process at apple has been time tested.
Macbook pros run the Core 2 Duos and runs fine. If you read the article about them it details the new 45 nm core 2 duo chips they are using.
They have engineers with years and years of experience doing these designs, it's not a bunch of kids in a garage somewhere making a suitcase into a PC and wondering why it catches on fire.
