I think the main reason is that the percentage of people playing games on it will be about the same as the percentage of PC users who play games on them, except the iphone + ipod touch total sales will never come near PC sales.
The 2 devices together are going to sell more than the PSP for sure, in the same way that there are probably more PCs sold each year than the PS2 sold in 8 years.
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Sony and MS are trying to add functions to their gaming devices to try make them more like music players/PCs etc.... but with PCs and the iphone it's the other way around, it's gaming functions being added to something with a different primary function.








