In my opinion, the biggest thing that Sony has going for them at this point is, they still have a serious price drop available as an option, without the confusion of having to decide how to price two or three different versions proportionately.
Dropping the PS3 to $249 or $199 would dramatically increase sales. For Microsoft to duplicate this, they would probably have to drop the arcade to at least $150, which would probably be awkward, as it would likely undercut sales of the other versions. OTOH, they could just discontinue the arcade and drop the price of the standard model to $199, so I don't know how much of an effect it would have. Still, from what I have seen, a price drop of the same dollar amount generally favors the more expensive console.
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