I've been arguing for the past year that Apple isn't stupid enough to discard the current MBA. It's still selling well, and the whole point of an extremely portable, battery-conserving machine is lost by adding a retina screen.
You trade off limited processing power and battery life just to deliver a "better" user experience. If I want the "better" user experience, I ought to buy a retina MacBook Pro and be done with it.
The point of the Air is portability and longevity. I'm unsure the next tier of processors will help much with either one. I can see Apple launching a new 12" product that incorporates a retina screen, eventually replacing the 13" "classic" MacBook Pro with something that's cheaper, more efficient and better suited to the legions of folks who use the classic machines.
I doubt very seriously that the 11" and 13" MacBook Airs will change much over the next several months.