The Hyperloop: hyper-sensation or hyper-hype?

So the day has come. The South African multimillionaire Elon Musk (the closest thing to a real-life Tony Stark, founder of SpaceX and co-founder of Tesla Motors) has announced plans to create a super-fast, super-safe method to communicate San Francisco and LA: a tube containing pressurized wind travelling at 600 mph, carrying "pods" which carry some people very fast - 30 minutes from SF to LA (even quicker than doing it by plane!)

Would you buy a used car from this guy?

The problem so far, is he has only Tweeted about it promising the design for today. Up to now, speculation is rife that this is only a bluff by the guy. Others, like me, like to be optimistic and think that he can, eventually, do it.

Will publish Hyperloop alpha design by Aug 12. Critical feedback for improvements would be much appreciated.
— Elon Musk (@elonmusk) July 15, 2013

Do you think he's bluffing or that it will happen?