Probably not at all in an airport terminal unless I'm stuck somewhere for an unusual amount of time. I rarely even pull out my MBP unless I have a good reason. Usually I just take care of emails, maybe play a quick game on my phone or a phone call if needed.I'm curious about this. Do you see yourself mainly using this in an airport terminal or on the plane?
On the plane? Maybe on long flights it might be nice to for movie watching or other tasks, but I don't see myself doing anything that would have me waving my hands about when I have to sit that close to others. Yes, much of the gesture controls are designed to work close to the body... Virtual keyboard still needs some work. I think the holy grail of this sort of spatial gesture recognition would be where I could type on a virtual keyboard without even looking at the keyboard... It's not there yet.
I see the primary advantage for when I'm actually at my destination. Be it at a client location, in a hotel room, whatever, I can have a virtual workspace with large displays. ...We'll see how it goes, but that sort of tech may just transform my home office as well.