@Alpha, but on the other hand if you estimate that the attachment rate will be half of what it was for previous Mario Kart titles such as the one on N64 (many did not enjoy the Mario Kart title on GameCube as much as the N64 and the Wii version seems to be letting go of the two riders per a kart aspect of the GameCube version), then you are still looking a solid attach rate and by the simExchange forecasts for hardware sales for Wii, then the lower attach rate would still result in sales that could match or surpass the current prediction for sales.
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