http://stopandmove.blogspot.fr/2013/08/hyperloop-proposal-ba...
It seems that the proposal is actully much less serious than on the first glance:
Amusingly enough, the California HSR budget for the Central Valley is under $10 billion. Ie, in the same ball-park as this proposal. The reason the HSR project is going to cost $60 billion is because it has to face an uncomfortable truth; actually getting to LA and SF is expensive. Very expensive.
Moreover, would you like to be sitting in the tube on the chair from which you can't even stand up for a half an hour without the chance to do anything but remain sitting, not getting any help the next half hour on the occasion when you get sick? Would you take your kid there? Your parent?
Designing mass transportation while ignoring such aspects is like programming without handling the limit cases "it works for N between 2 and 100 but not for 0, 1 and MAX_INT, even if these are allowed inputs." It's bad, very bad for the user, only an "astronaut developer" can love such a solution.
The first time a kid dies because it got sick the first minute of a 30-minute ride, the project is dead for good. Imagine the press, imagine the public response.
I can imagine entering the capsule to reach the international space station, preparing a whole year before. I can't imagine doing the same preparations for the ride between SF and LA. Give me the real train, thank you.
The public seems to have no issue with that concept, it is a simple risk that goes with getting on the train.