As you can see in the trailer, the next Zelda game for the Nintendo DS looks a lot like the last Zelda game for the Nintendo DS. From the press release:

The new The Legend of Zelda™: Spirit Tracks game...will utilize the intuitive touch control of Phantom Hourglass in an all new adventure that will please longtime Zelda™ fans while keeping the game accessible to all DS owners. The concept behind this Zelda game includes utilizing a steam locomotive to travel around the world, switching Phantom and Link to explore the dungeons, and solving puzzles using new items.

As much as I try to maintain a healthy cynicism, I'm constantly impressed at how many Zelda games Nintendo can crank out, each little more than a variation on the same formula, but each strangely compelling. New Mario games do nothing for me, but for some magical Nintendo reason, I'm a little atwitter at the announcement of any new Zelda game.