We reported last week that New Super Mario Bros. Wii had sold over 400,000 units in its first day on store shelves.  Now it has almost cleared the 1 million mark in its first 4 days, making it the fastest selling Wii game ever in Japan!  The game even beat out New Super Mario Bros. DS’ mark of just under 900,000.  If these sales continue, we could see New Super Mario Bros. Wii become the best selling Wii game in Japan!

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