I'd like to see Nintendo ditch the extra screen or make both touch screens. I don't think dual screens are really relevant in the current market. If Nintendo does ditch the second screen then I want a multitouch screen that is pressure sensative. Virtual Console for the handhelds. Really I want a new GameBoy not a new DS. I want something like the I-Pod Touch meets the PSP.
Visually I want GameCube graphics maybe even as high as Wii visuals. I want improved audio when compared to the DS. I want a headset like the one the DS has to come bundled with every console or a built in microphone for interactive gaming. A webcam built in so that you can video chat in games like can you imagine battling a friend and seeing your friends face while you kick his butt? A tilt sensor would also impress me making the device a true successor to both the GBA and the DS.
In other words I want a state of the art handheld!
-JC7
"In God We Trust - In Games We Play " - Joel Reimer