It's a way to simulate a weakened magnet by moving it farther away from the strings. It's more evolution than revolution.
You could ask the same question of manufacturers who "age" their magnets. What will an antiquity sound like 50 years from now? That being said I don't buy into the idea that magnets naturally age and break down. The elements that make a magnet are stable, so there shouldn't be any degradation. However if you expose the magnets to strong electromagnetic fields they will degaus.but the question is.. in 30 years from now when the magnet does age.. how will it sound? even weaker? will it loose definition? are people gonna mod their air buckers to remove the "air technology" and make em regular buckers? :scratchch
I have never liked the "Air patent" pickups because they sound weak to me
Also, the "Dual resonance patent" ones seem to sound a bit weird, especially when picking hard, and they tend to color the guitar's tone too much to my liking (Evo, Tone-Zone, D-Sonic, etc.).
Still, Dimarzio makes awesome "no-patent" pickups like the PAF-Pro, X2N, Breed...
I have never quite understood why airbuckers should sound any different to just lowering the pickup a little.