Went with the Air
Made my decision and purchased a refurbished 2012 MBA.
8GB ram, i7, and 256gb SSD for $1450.
My current Air is is the 2010 ultimate. I love this machine to death, however, the CPU is dated, and 4gb is no longer good enough.
Yes, I probably would have bought the 13 rMBP if it had a dedicated GPU.
I also felt uncomfortable about the PRO 13" GPU. I am not sure how good the intel chipset would handle the retina display, and at Retina resolution I'll lose screen real estate compared with the Air. Finally, I usually end up connecting my air to an external monitor anyway (at home and office), so I believe that the retina screen will have limited value for my use case. Once they release a Retina cinema display, I'll be the first one to order it. While I decided not to order a laptop with it today, there's no doubt that the retina screen is dead gorgeous.
As for rMBA -> I don't see how apple would fit it into MBA with the current spec of the 13 rMBP. Other than the screen, there's little to no real difference between the Pro and the Air. It will confuse clients, and will only frustrate future owners, since it will be hard to make a purchasing decision.
From my perspective, I think that apple will end up with two lines:
Airs: 11,13
Pro: 13,15
Pros will carry the retina, until there's going to be something else that can differentiate it from the airs.
In any case, I've saved the $500 price difference on the retina today, and will use that for future upgrades (if and when the right product comes along).