What you have to realize is that Zelda is no throw together. They really take their time developing the game, I mean, they REALLY take time to work on it. That's what keeps Zelda going so strong, I think.
There are always many things unique about each one, so it wouldn't surprise me if it took three or so years for another release.
Currently Playing: Lunar Knights
Videogames like...run through my blood. Leik srsly.
Next on the list: FE:Path of Radiance (SHAH I'm lame and still haven't gotten it. XD)