Same thing happened to me. Not a speck of dust in between but the bottom is slightly skewed to the left. Hardly noticeable but of course it's bothering me that it's not perfectly centered. It's a bitch putting any screen overlay on a white iPhone and can't see the borderlines.
I ordered another the other day on the 40% off deal so perhaps I'll take another shot at it. I can't help being a perfectionist.
And I tried twice at the button sticker but it's pretty lame. Left it off.
Yay, my little speck is gone, so I guess it was a tiny bubble. I ordered a Bodyguardz Pure at half price for a day when I decide the offset bugs me enough, or I scratch it, or whatevs. I'm really loving this glass protector, it will be hard to ever go back to anything less.