It has 2 screens, the top one is 3.5 inch and is the one that uses the 3D technology, the down one , 3.02 inch, is touch screen, but no 3D, because the touch would affect the 3D effect. You can play your original Nintendo DS Games, it has a new feature, like an analog stick called Slide Pat, a slider on the side that adjust the 3D effect. It ca play 3D movies and takes picuter in 3D using 2 0.3 megapixels cameras in the front of the handheld.
The Nintendo 3DS cartridges will hold 2GB of game data and look almost exactly the same as those of the current DS. However, there is a small tab jutting out on the one side, most likely to prevent 3DS cards from being inserted in the 1st generation DS. The Graphics can be compared with the Wii graphics.
The 3DS possesses Wi-Fi capabilities and periodically searches for Wi-Fi hotspots and other 3DSs without user input, and will be able to receive data from the Internet or other 3DSs while in sleep mode. The system supports multiplayer gameplay via a local wireless connection or over the Internet
TL:DR The thing that will kill the PSP and dance on his grave
Gamer two: Dude, i was at E3, i saw it, and yes, i will buy it the first day.