EA: The Zelda team is already planning Four Swords for the Nintendo DS. This game will have a lot of connectivity and feature a lot of interaction between both screens. It will be interesting.
EA: Like I said, we are working hard to add a lot more details to the graphical engine. In fact, working with this realistic Zelda title is far easier than what we did with Wind Waker, which was harder to do. Believe it or not!
I think Four Swords will become the "Mario Bros. Classic" equivalent of the Zelda portable series. I'd be very surprised if Minish Cap didn't have the original Four Swords in it.
A 3D FS sounds like it'd be really hard to do. The best option would be a MM/OoT MMORPG instead of a 3D FS, IMO.
With the next console Zelda being easier to develop (program?), I hope it looks better too, and they can focus on other aspects of the game (dungeons, bosses, etc), as well as making the graphics look detailed.