I predict that air gestures will spread not as a replacement for existing interaction methods, but as an alternative for achieving specific purposes.
I think that Shota is right about air gestures not becoming a replacement for physically swiping or using a mouse, because using air gestures can only be functional for so many things and this method doesn't encompass the full functionalities that physically tapping and swiping do. It seems like developing the technologies to perfect this method would likely be very expensive and it probably would not be worth it in the long run for general usage. Overall, air gestures may present benefits in certain use cases, but they will likely not overtake traditional methods of interaction.