I'm gonna say 2011, right before the end of Wii.
Look how long it took to make TP. Again they will want to do something different and they're probably making a new engine to do it. As we all know TP was using tWW's engine but highly modified.

This will be the first Zelda game actually made for Wii, so there will be a ton of new code to produce. I just hope Nintendo see the goldmine behind each Zelda game and keep making them better, that's why they need more people working on them to get it out faster.

I'm not really sure if I want Ganon again, they pulled off a nice Man-to-Man sword combat in TP which was really satisfying.

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