Only the iPhone 4 and iPod touch 4G (iPt4) have the Retina high resolution (960 x 640) screen. The iPod touch 1G, 2G, and 3G have the low resolution (480 x 320) screen.

I've got a iPt4. I love it except for the lackluster battery life. I used it a lot before I got a good smartphone (Motorola Atrix 4G), now I use the phone for everything and the iPt4 sits on a shelf collecting dust. Like I said I love the iPt4 and used it prior to getting a good smartphone, but I prefer everything to be in one device. I always hated carrying two devices. I never considered the iPhone as every friend and family member who has one has difficulty holding calls and their iPhones sound terrible when you talk to them. It is a joke around here that if the person you were talking to was not hearable or kept losing their connection, they most be on an iPhone.