Microsoft has apparently upped the Gamerscore limit an Xbox 360 game can award a player, with the maximum now standing at 1750G and 80 Achievements for a full retail game.
This news also seems to "confirm" inadvertently, that there will be no more DLC for Halo 3, because the game has already reached the 1750G, and DLC will be without any achievements, but I doubt it
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