There looks to be a really weird bug or faulty hardware in the Verizon Galaxy Nexus that's screwing with multitouch. When you hold down the top left corner of the screen, the bottom of the screen doesn't register any input.
It's so completely weird. According to the user who filmed the video, the problem only exists when the Galaxy Nexus is held upright in landscape mode and doesn't exist in other positions. That particular landscape position, however, is especially annoying because when you play games with overlay controls, the dead points are where the joystick and buttons are. Also interesting: if you turn the screen on/off, the problem will go away.