From my experience business travel is as much about sharing an experience as it is the discussion or dissemination of information. That's a hard thing to replicate
Until technology can replicate the experience of staying out late, drunkenly chatting with coworkers in the back of a taxicab as you ride through Manhattan, then grabbing a midnight snack at a hole-in-the-wall diner someone recommended back at the office, business travel will have its place.
My theory is that physical proximity means danger or love to our animal brains .. and knowing it's tech will disengage your brain from feeling close and will change your emotions and engagement to the other person. Now something more natural than a LCD screen might make video calls a bit more lively and efficient.