There have been many variations of these basic ideas for a while. Hyperloop is different in that it does not require a full vacuum, but just a low-pressure atm

There have been many variations of these basic ideas for a while. Hyperloop is different in that it does not require a full vacuum, but just a low-pressure atmosphere, which make the tubes much cheaper to build an maintain. It also does not require magnetic levitation along the full length of the tube (like the Chinese proposal uses), as it uses an air cushion provided by that a compressor that sucks in that low-pressure atmosphere, further reducing the cost of building the tube. It merely uses occasional magnetic linear motors spaced out along the route to accelerate and decelerate the pod, spending most of its time coasting on its air cushion. So, while it does share design features with many previously proposed systems, it is not exactly the same as what has been proposed before. There's a good reason why people have been talking about evacuated tube transport for centuries but no one has actually achieved it on a practical scale; the hope is that the low-pressure design will be much cheaper than the evacuated tube design. Now, I am somewhat skeptical of the incredibly low numbers that Elon Musk quotes, especially relative to the much more well understood high-speed rail he's comparing it to. But you shouldn't dismiss it just because there are some superficial similarities to previously proposed systems; as far as I know (and I haven't done much research, so I could be wrong), this is the first such system that proposes using low pressure, a compressor on the front of the pod to deal with the problem of the air mass not being able to flow around it, and an air cushion to support the pod taking advantage of the air taken in by the compressor.