I, for one, would love mutliplayer in a 3D Zelda. Because I have played Spinter Cell: Chaos Theory (Xbox, other versions not worth mention).

Cooperative actions in 3D as seen in that title would be way improved with some co-op item puzzles, like using a Hookshot on a wooden shield to meet your P2 across a gap or shooting your arrow through his torch to melt an unreachable ice block.
I can come up with like a billion more of these off the top of my head, several of which seem cooler in 3D than they would be in 2D, and they'd all be awesome.

__________________