I guess it could depend on your definition of "glide", but I doubt that anything gliding at supersonic speed would have a very good glide ratio. Thus, it would

I guess it could depend on your definition of "glide", but I doubt that anything gliding at supersonic speed would have a very good glide ratio. Thus, it wouldn't really cover much ground even thought it might travel quite a bit vertically. If we consider the reason one wants to travel at supersonic speeds, we might arrive at something involving the value of a human's time. Given that, slow but ultra efficient, luxurious (and internet-connected - "workable") travel might be something. Then gliding, floating, etc. with ample space and creature comforts could be the focus.