I call BS on the reason cited in the link: The pressure inside the sealed glass envelope cannot "increase" due to a drop in external pressure. If anything, I would think that the reduction in air pressure would cause the glass envelope to expand outwards at the surface (let's see: air pressure drops approximately 1 pound/square inch for each 1000 feet above sea level, so at Denver, lets just call it an even 5 lbs./in², spread over a 50" 16:9 plasma screen (~1065 in²) yields somewhat on the order of 2.6 tons pushing outwards on the plasma set's glass screen in the Mile High city.) The distance between the front and rear electrodes would increase some small amount which might be what causes the increase in power consumption the weblink indicates.
However, I thought that the pressure inside a plasma set was lower than 14.7 lb./in², which doesn't change the math, it just indicates that the glass in a plasma set needs to be extremely strong.
