I would find it unlikely that Apple will be abandoning the Intel chips for its computers. However, a good long look at Apple's latter-day business success points more closely to the success of the iPod, iPhone, and the like. Sure, Macs do make a significant amount of money, but the iPod and iPhone are what paves the way toward new innovation. Computers change less dramatically, but the market for personal micro-computers (iPhone-like PDAs, or tablets) is the future. Apple wants to go to where the puck is going, not where it has already been, right?
I imagine Apple is looking closely at the replacement of the laptop. As soon as it is possible to smash the power of a Macbook Pro into something about 1.5x as large as the iPhone, the nature of personal computing will be profoundly changed. People will connect it to their 30" monitors or 50" LCD TV's at home, and when they are out and about they will use their iPhone-like thing. Seems like a logical progression to me. In order for this to work, low power will be critical. Today's acquisition is moving in that direction.
Wonderful time to be an Apple fan, and what an exciting time to be a computer enthusiast!