My Nexus 7 died. I didn't see it happening. My son was playing, went to school and left it charging. At night it didn't turn on anymore. The screen is black.
I've followed the Asus instructions. This answer says to disconnect the battery. Any other tip? Nexus isn't officially sold in my country (Brazil). I'm afraid I won't get be able to use the warranty.
Since the last update, I've noticed some hiccups. Maybe it was due to excess of running applications.