Ok, first of all that makes no sense at all - it might need to sell a XXX copies it's first QUARTER so that investors don't worry that costs might not be recouped, maybe even XXX+XXX copies by the end of the fiscal year, but there would be absolutely no reason it would HAVE to sell a certain number of copies it's first day. That has no bearing on anything.
Payton notes that the figure may be hard to reach due to the PS3's relatively low installed base
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We're telling our fans that if you want to play Metal Gear Solid 4, you have to buy a PS3,"
That kind of seems like more the message of the article - if MGS4 plans to make a tidy profit, more people need to buy PS3s. This kind of gives them another excuse to mention that it's an exclusive for the time being. Even if a 360 port is in the works, chances are it won't see the light of day for a year or two, and Konami obviously wants to sell as many PS3 versions as they can so that they can move out of the red on the game and into the black sooner rather than later.