Coming from an IGN article…

A lack of information from North America. This is Japan’s show and everything that will be coming out of Japan will be for that territory …
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Cambridge, Mass. – Sept. 24, 2010 – Harmonix and MTV Games today announced that a five pack of Anthrax songs, plus tracks from The Doobie Brothers, My Chemical Romance, 30 …
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Here, here, Team Ninja

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This is said to come from a source inside the game industry. Just remember this is just  a rumor for now.

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