Gabe's had to replace a couple Xboxes, and there were well over a hundred at PAX, and we've never seen one catch on fire, or shoot lava out the back, or whip its power cord around like a scorpion tail. But the mental images generated by this Boomtown article were too rich to pass up. It's my understanding that there have been thirty or so cases out of 14.1 million units shipped, so it seems unlikely your entertainment center will become a tower of flame anytime in the next ten minutes.
