...Tempted to say CoD4/MW2, at least given the amount of impact they seem to have had on the whole. However, I'm not sure how well they'll be thought of after a decent amount of time has passed. I'd say FFVII and, to a slightly lesser extent, OoT are up there too, though I do like them both.
On this board, I'd say FFIX, but that's almost certainly a very unpopular opinion.
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xp1337: Don't you wish there was a spell-checker that told you when you a word out?
GotD (219/384) Melee v FFX