My original Evo and my 3D had no light leakage but sadly my new Evo LTE has some in the center. It's not as bad as some pictures I've seen but it's definitely noticeable on black screens.
Here is a picture of someone's light leakage that was posted on another forum:
He noticed that the one that had problems was from a box with a large security seal sticker. His 2nd Evo had a smaller sticker (we are assuming they are from 2 different assembly lines) and did not have the light leakage problem. I checked my box and it also has the larger sticker. For those of you who have the light leakage problem...do you also have the larger sticker? It would be interesting to gather a larger sample size to see if there is a direct correlation.
Here's a pic of the 2 stickers: