Earlier this year, before the first MacWorld of 2002, I predicted Apple would move to a different sort of model tiering. I predicted that Apple would go to dual G4's in power systems, and put powerful single G4's in desktop models in order to compete until the G5 (which I've been saying for the past few months would likely be made as the IBM Power4 in the new ultra-fab they just made) was ready to ship.
And it makes perfect sense for Apple to go to a single/multi tiering system for consumer and power system sales. It's the most sensible method that allows them to continue ramping up performance on both the consumer and professional level systems without artificially holding back power like they have for the past several years.