Shigeru Miyamoto wrote:“We’re focused on providing a robust line-up of Wii U software for next year. It seems like we’ve managed to do that this year and people are very happy with what we’ve done on Wii U. For the time being, our focus is on the Wii U hardware, but Nintendo as a whole has groups working on ideas for new hardware systems. While we’re busy working on software for the Wii U, we have production lines that are working on ideas for what the next system might be.”
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I'll be interested to see what happens next.