Yes, Hyperloop Transportation Technologies exists (I'm volunteer), they are going to design and build a prototipe using crowdsourcing engineering (not capital as far as I know). Also they have contact with several universities and companies that are interested in partnering and developint part of the systems. Right now they are working in the legal parts of the company and mean while there is a brainstorming at the engineering part with calculations beyond tha alpha document. It's a hard process as the technology is so new, but amazing non the less. The idea is to start building and testing a scale prototipe for 2015 in LA.

There was a time when maglev was a theory - until it was tested, prototyped, and implemented. Let's wait and see. If we said "but it's never been done!" to every new idea, we'd be lacking a lot of interesting/important thing.

Elon Musk's Hyperloop makes sense from first principles. Most people and therefore most governments don't think that way.