Due to the size of the wii game discs I'm sure we can expect to see a longer game than TP, I just can't see the game being short this time around. they have put years of work into this game and hopefully that will show in the length of Link's new adventure. Whether the setting for the game is wide and sprawling or smaller and more condensed im convinced the story line and plot will surpass that of the previous console titles. Or at least it should. This is truely a next gen Zelda. and not just like OoT to MM, (in terms of game size the two were pretty much equal: 25MB vs 26M

this game will be significantly larger than TP and WW both of which were massive Zelda games. The difference this time will be measured in GB (1.4 GB vs 4.7/8.54 GB if dual layered) which is quite a leap.
However there are a few factors (like the new controls) that could decrease the overall size of the game, though I don't think those factors are enough to limit the game to about 30 hours like TP. Zelda Wii should, in theory be around 100 hours if not longer, because Wii game discs are about 3.35 times larger at the minimum! Even if the new controls take up massive space they have plently left to work with.
It's important that they give us a full fledged Zelda game after what they did to us last year... just showing a piece of art!... and letting us destroy are minds trying to figure it out! for a whole year i was flippin out. Now I'm ready to pwn their game cause im so pumped up for it. If that was thier plan then it worked, but man im so ready! Thinking about Monster Hunter Tri, I'm pretty sure that they wanted to have the new graphics up to that level or something... if MHT is any indication of how far they have come with the Wii (and from what I've seen and heard that game is huge!) then Zelda Wii should be too.