Mine is bowed up in the center. I have to use a fingernail to push the nook button.
As much as I like the rest of it. I deal with it.
If a perfect device was 100%... I guess with a point off for lack of GPS and another couple for mic and camera. and then another for the little black plastic strip at the bottom of the screen. Then of course the Micro USB pain in the butt to plug in to charge I take two for that. I would say I rate my Nook Color at a 94% overall. That is a great score for a great device in my opinion.