Just to add a company took the name and is trying to build something else. https://hyperloop-one.com. There has also been a lot of ideas on these lines. What made the original design different was low vaccume* which is vastly cheaper than high vaccume, and using the fan on front and ground effects to effectivly fly vs maglev or traditional rail.

Note in this context high vaccume is hard, low vaccume is cheap. http://www.npl.co.uk/reference/faqs/what-do-high-vacuum-and-...