My guess would be that eventually all Apple devices will have Retina displays. But doing a search seems to imply this won't happen for the Macbook Air until at least the next generation, a six to nine month wait minimum. Personally, if I delayed my computer purchase waiting for the next generation, I'd still be using my Etch-A-Sketch.
It is not quite related to the topic per se, because it has to do with resale values. If you look at eBay, a mid2010 or mid2011 MBA are typically priced around $600-ish...and yet seems to have very very very few people interested. I wonder if it is because the resale value isn't matching seller's expectations of $600? On the other hand, if you look at MBP, I find the resale demand is much higher. Thus, this may play into your decision into buying a MBA at all to begin with..(that is especially if you believe you will sell off your "old" MBA one day in the future)
It's completely up to you; I don't think the MBA will get a retina display any time soon. If you want to wait until the 2014 model comes out (most likely without a retina display) that's up to you. Or spend a couple $$$ more for a MBP with retina. Like I wrote, up to you.
I think you should wait....the retina display works great ..most of all most it will support beeter apps, and they do work great on it, the display is awesome...
Air w/Retina may be a greatest thing Apple produced since iPhone, but I guess it can easily kill a lot of tablet sales. Who need a tablet if a laptop with just the same mass and much more power will be available on market? But if Air with Retina will be released it will be my next laptop undoubtedly!
now it is Macbook without Air has Retina display, and thinner than Air...... so I guees Air becomes the cheapest Apple mobile computer available now.