The problem is that GTA4 is for two consoles, not 1. No matter how hyped or stellar the game is, it's still a multiplatform game. This is going to leech off potential sales of both the PS3 and X360 as people aren't going to have a single clear choice of console if they really want this game.
As for price drops, Nintendo hasn't started a single one! Who's to say they can't perform a price drop in response to their competitors. When it comes to lowering the price, the company who lowers last often wins.
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