I wonder if Apple is simplifying their product line with the iPhone 5C... Right now the carriers sell three iPhone generations: the 4, 4S, and 5. Obviously the new flagship will be the 5S, but I'm thinking the 5C will replace all previous generations as the new low-end option, leaving only two generations to be sold. If the 5C really comes in at $400 (contract-free), then it would be at the "free with contract" price point, so why keep anything less expensive in the lineup?
Then they would only manufacture 2 generations of phones, both standardized on the new taller aspect ratio, Lightning connector, and LTE. I would expect they'll only offer the 5C in one storage capacity. That would reduce the total number of SKUs that they have to manage, which would make it easier to manage all the new SKUs with the various new color options.
I'm thinking that managing essentially two different models (5S and 5C), even in numerous colors, would be easier to manage, since the internals for a given model are the same, and it's just the housings that you have to make differently (even then, it's the same part, just different color). Managing three different generations means there are hundreds of internal parts you have to manage separately, all the different chips and circuits and switches and cables that are different between generations.