[chriswarbo]

I don't see something like this scaling in the way that a rail network can. Shuttling a few people at a time won't be enough for morning/evening rush hour, you'd need loads of these to match the carrying capacity of a train, and then you've reinvented the problem of traffic (although presumably much less dense; e.g. I imagine you'd join a queue and have to wait until the airspace isn't congested before your journey is permitted).

That's also an optimistic outlook. One contributor to traffic is people using a whole car just for themselves; since we've not figured that out after several decades of having cars, I doubt making them fly will solve the problem.

I can imagine niches for this, and wish them luck, but I don't think it'll make a dent in mass commuter transport.