Jumping from a 1st generation to the upcoming 4th generation iPod touch, I can't wait!
I'd be really disappointed if the 4G will not get a camera since I've been waiting for 3 years now. I prefer a camera on the back because I know I won't bother using FaceTime and because I hardly have Wi-Fi here. Even if it doesn't get a camera, I have to upgrade anyways because I want the iOS 4.
Also, my iPod Classic (4th generation) recently died on me

So I'm using my iPod touch fulltime and what I really miss is a simple next/pause button.
The volume buttons on the current iPod touch, I really would have prefered them functioning as next/pause buttons more rather than adjusting the volume (an official setting, letting the user decide whether they want it to function as volume buttons or next/pause buttons would be great!). I don't have/want those Apple earphones cause they are crappy quality
I guess this is my little and quite simple wishlist for the 4G!