My new 32GB iPhone 4 seems to have an issue where the screen flickers/flashes (looks like the brightness is going up and down), but only when I am in a phone call, (holding the phone away from my face so the screen is on), and only when it is also transmitting data (I can see the spinner rotating). Anyone else run into this? OP, is this what you were experiencing, or something different?
I have the same thing as well. It is a very persistent flicker with flashing horizontal lines on the whole display.
My screen flickers when I slide from my second page of apps to my first. Everytime...