the screen is insane. worth upgrading for that alone:
The best display ever on a mobile device.
Everything you do with iPad, you do through its large, beautiful display. And when the display is better, the entire iPad experience is better. The Retina display on the new iPad features a 2048-by-1536 resolution, 44 percent greater color saturation, and an astounding 3.1 million pixels — in the same 9.7-inch space. That’s four times the number of pixels in iPad 2 and a million more than an HDTV. Those pixels are so close together, your eyes can’t discern individual ones at a normal viewing distance. When you can’t see the pixels, you see the whole picture. Or article. Or game. In ways you never could before.