I have always maintained that MGS is a a hardcore game for hardcore gamers, it is not the game that is going to make people buy more PS3's any more than portable ops did for the PSP.
I am sure it will be an outstanding game, potentially best of its genre, but I don't think people who don't already own a playstation 3 or have an affection for the franchise will suddenly become converts. There will of course be a very small percentage of PS3 fans who are waiting for MGS4 to release before they invest in their console but we are not talking about the sort of numbers that will make a huge impact on Sony's level of market penetration.
Something else that nobody seems to get is that the PS3 does have two exclusive franchises that appeal to a huge aray of gamers and that neither Microsoft or Nintendo can match. What are they? Singstar and Buzz. To a gamer interested in shooters, stealth and racing games these might not seem important but in terms of hooking the casual market not even the Wii has anything that comes close.
If I was Sony and was looking to turn around my fortunes those are the games and the customers I would be looking to snare (like the PS2 has done with the same games.) A 350-400 dollar package that includes one or both of the games would have much more people buying the PS3 than the same bundle with MGS 4 if you ask me (even though MGS 4 is the game that I personally would prefer).
Games like MGS4, GT and Killzone 2 will work wonders for the PS3's attachment rate but actual console sales, I'm thinking not so much.
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