[ghaff]

And at some point, if you can make 20 or 24 hours of flying comfortable enough and maybe have good enough communication systems, who cares? (OK, there are a few people who want to go back and forth to Japan in the least time possible. But, let's get real. Air Force One isn't a supersonic jet.)

It's mostly a case of dialing in the space and price per passenger for the market. Given enough space and entertainment options--hey, live performances in the lounge!, celebrity chefs--very few of us really care that much about getting to a destination 12 hours faster.