Anything good you've read that explains why they've abandoned that route?
The "flying height" in the original proposal was to be about 1mm, so this thing has to be really well behaved aerodynamically. And the tube has to be really smooth. (Expansion joints, emergency escape hatches, pressure doors, and switches would be problems.) The whole point of the Hyperloop is that it's cheap because the tube is simple and dumb.
When you look at the MIT design [2] it's really a maglev monorail that operates in an evacuated tube. (Or outside of one, as they've demonstrated by sending down a rail). It doesn't have any of the fan propulsion or air cushion lift or tight tolerances from the original Hyperloop proposal.
[1] http://www.ansys-blog.com/20130925hyperloop/ [2] https://www.youtube.com/watch?v=yiyPQU48Ef0
A maglev system needs a much more expensive track and/or a lot of energy from the vehicle to power the lift. This is the big problem with maglev - track cost. Maglev works fine; the Transrapid system in Shanghai has been running for 12 years now without serious problems. Top speed 300 MPH.
The Hyperloop is only interesting if it's far cheaper than a maglev. The Transrapid maglev system has far more capacity, can corner better, and can climb steeper grades.