While they can use the bus speed to differentiate (some 1333 and some 1600 - crippling one of the most significant bottlenecks using today's software), if they go all 8-core at MacWorld, there won't really be much between the various offerings. The current 8-core is nearly £1000 ($2000) more than the 2.66 4-core at the moment, and offers some users a compelling reason to choose the high-end model. If all models are 8-core, including a 2.83 at $2499, while the choice of that processor can be justified (same cost as current dual-2.66), it seems somewhat unlikely that Apple will gut the cash cow of the lineup to sell more base models. Further, do they really need to keep selling workstations for so much less than the competition now that Apple is regaining market share? What do you expect to see at MacWorld? We have a lot of people here counting on an all 8-core lineup based on Multi's math, but he has not turned out to be the great prognosticator we had thought. Are you?