@JRigby, thanks for submitting. I agree with Laoldar that it will not be the final boxart. It looks like an early placeholder graphic. All those sites (Amazon, EBGames, Gamespot) will post placeholders from time to time until the actual product packaging is determined.
For one thing, it looks nothing like every other Wii game released in terms of border. Also, Nintendo dropped the "only for" purple corner and it hasn't appeared on any Wii games.
No idea why Gamespot has that up, but it's definitely not the box art.
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