It's the screen. My main motivation for upgrading to from the iPhone 3GS to the 4 was the Retina display, and it was important to me because I do a ton of readi

It's the screen. My main motivation for upgrading to from the iPhone 3GS to the 4 was the Retina display, and it was important to me because I do a ton of reading on my phone. Much of it in Instapaper, actually.