Geometry Wars PC!

[Dark Jaguar]

Eh, depends on how you look at it. DirectX basically doesn't see "2D", at least not in a direct sense. It's a single API. If you want to do a 2D game, you do it as a big texture sheet. Now, it is just a bit tougher to get it going in some ways, but there are some clear advantages, and one of them is that since the entire 2D game is basically a texture, you can do everything you normally could to that texture. For example, distort, rotate, zoom, which geometry wars does to great effect. If they so wished they could rotate it around so you saw it from the "back side" or at an angle, all without much effort at all.

The real question is how well it would translate to the DS, if they could still do it as a 2D layer in 3D space, allowing for all those well done distortions. It's not just that though, a number of the special effects involving pretty colors are done in interesting ways that suggest a 3D nature (though scrolling around doesn't really make "forground" elements of them move parallax). Certainly though, the starry background has a bit of parralax to it, suggesting 3D.

Anyway, in the end the game is clearly 2D gameplay, and depending on the power of the DS, they might have to knock out a lot of those effects and just do the game 2D in the back end as well.