If the 4DS (I hate that name) comes out in the next 2 years or so, it should be AT LEAST equivalent to mid/high-end smartphones of today (which currently retail for $400-500). So I want at least 3GB of RAM, a 720p (main) display at the absolute minimum and a solid quad-core CPU.
Good battery life is a must, too.
Hardware owned:
PC, PS4, 3DS, Wii, Xbox 360, PS3
Most anticipated games (near to mid future):
Zelda U/NX
The Last Guardian