I own systems from all three companies, but I have to say, if any system was going to get me laid, it'd be my Wiis.
For one, non-gamer girls typically like Wii more.
Two, the stereotypical "hardcore gamer" is typically unappealing to girls, and the PS3 and 360 have a larger percentage of their userbase filed with said stereotypical gamer. Granted, the Wii has a larger number of oldschool gamers, and the oldschool gamers tend to be the worst of the hardcore gamers, but I find that detail is slightly less an issue after all is said and done.
Put both of these together, and it's very clearly advantage - Wii.
For me, none of the above applies anyways because I'm married.
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