Businessweek's Ashlee Vance reported the Hyperloop details today, revealing that the aluminum tubes would follow I-75 between Los Angeles and San Francisco. "The pods would be mounted on thin skis made out of inconel, a trusted alloy of SpaceX that can withstand high pressure and heat," Vance wrote. Air would get pumped through tiny holes in the inconel skis to create an air cushion, and it would get there via an electric turbo compressor. An electromagnetic pulse would each pod an initial thrust.
Musk told Vance that the Hyperloop was designed to link densely populated cities less than 1,000 miles apart. "It makes sense for things like L.A. to San Francisco, New York to D.C., New York to Boston," Musk said. "Over 1,000 miles, the tube cost starts to become prohibitive, and you don't want tubes every which way. You don't want to live in Tube Land."
As for how such a system will actually be built, Musk has been hesitant to toss his own hat into the ring, calling the Hyperloop something he's putting out there as an open-source design. Last week during a Tesla Motors call with investors he said, "I think I shot myself in the foot by ever mentioning the Hyperloop. I'm too strung out."