Interesting concept--but not a train
The two examples definitely point out the advantages of a ground-effects vehicle, but that technology is anything but new; the only difference is by offering a 'hard' track for it to fly in. A simple search in Google Images for Ground Effect Aircraft displays numerous prototypes and operational GEA that have been around for decades. That said, those same video examples point out the disadvantages of stability that could make the passengers seasick (or airsick) at best. Without some form of physical stabilization, an airborne vehicle in a channel is more at risk of crashing into the sides or deck of the channel than it is of flying comfortably or smoothly within that channel. A much more efficient method would be a cylindrical vehicle in a tube since the air would be forced to move equally around all sides--though again you would fight compression drag which is what this concept is supposedly trying to eliminate.
Secondly, a "train" is a number of vehicles/wagons physically linked to each other, and neither of these concepts begins to demonstrate this definition. Most monorails and current maglev trains exemplify this definition through an articulated vehicle able to bend through curves, something the current ground-effects vehicles seem unable to perform. Rigidity is needed to help maintain a 'wings-level' attitude on the straight stretches yet flexibility is needed to allow each segment to bank into a turn smoothly and independently. In essence, the two requirements are mutually incompatible. This isn't to say such a concept is impossible, but gyroscopic precession is about the only reliable method I can imagine with each 'car' independently equipped. Said gyroscopic precession could also stabilize the combined vehicle better than any rail or guide system. The drawback to this concept is that the gyroscopes would have to be comparatively massive to overcome the inertia of the vehicle itself at speed.
