This looks like a neat idea. However, I had to chuckle when I read this paragraph:
"During the flight, passengers would peer at national landmarks just 8,000 feet below or, if they weren't captivated by the view, the cavernous interior would easily accommodate such amenities as luxury staterooms, restaurants, even a casino."R-i-i-i-g-h-t. I doubt it. Instead of having all of these luxuries on board, the companies running these things will most likely just jam another 5,000 seats on them. However, this might have the side effect of providing a really cheap (if slow) method of transcontinental travel.