Since this will probably be the last Halo that Bungie produces for the xbox 360, I would imagine Microsoft will have a crazy launch like they did for Halo3. Commercials everywhere and adverts on pop cans. If this is the case I would imagine Halo will trounce GT5 atleast the first few months.
So I think Halo will take the cake in first week and overall sales. I would imagine that Meta will be slightly higher with Halo as well.
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