You mean this problem?
http://forum.ppcgeeks.com/showthread.php?t=130284
Exchange the phone...Trust me..I just got my new one and this problem is now gone!!! I came so close to throwing the phone into a wall!!
I can tell you when I compared the two screens side by side my old screen looked like crap when viewing black. I couldn't believe it till I compared it right next to my new phone. The problem was also happened more when I would plug it in with a aftermarket charger..It also started doing it with the charger that came with the phone but not as bad.