The wi-fi that is available on US domestic carriers (eg Virgin America) is cost effective because they are using base stations on the ground under where they are flying. One of the reasons Connexion was killed was that the satellite costs were too high. So most international carriers who do their flying over water won't be able to utilise the technology used by US domestic carriers.

I believe the base stations are separate to the GSM signal and specially setup for GoGo. But I might be wrong about that.