I think the retina display will come to the Airs in 2014. Apple really wants the Air to be its consumer laptop. If somebody wants a retina display Macbook, the 13 rMBP will be the answer for 2012 and 2013.
I see your point. It may not make a lot of sense from what seems to be Apple's current strategy of segmenting products in the market.
But, again, Apple may want it, but this will depend on what the competitors will do as well. There are already lots of ultrabooks/convertibles which are available or to be released soon, featuring a 1920x1080 resolution IPS display (Asus Zenbook Prime, Acer Aspire S7, Dell XPS 12, Microsoft Surface Pro, Asus Taichi, Acer Iconia W700, Samsung SmartPC Pro, etc.). Apple's MacBook Air is behind all of them in terms of screen quality and resolution.
Next year, after Haswell comes up with its power-saving abilities and a much better integrated video card, manufacturers will release ultrabooks with 2560x1440 resolutions. Samsung has a Series 9 prototype which was shown in August 2012; it is unlikely that this particular ultrabook will not see the light of day within one year from now.
Then, you have Apple's MacBook Air. Apple is proudly announcing the retina MacBook Pros as the highest-resolution laptops in the world. The retina iPhone and iPad were also widely announced as top devices with killer screens, before anybody else could deliver that. It would be weird for Apple to have a low-resolution ultrabook when everybody else is quickly moving towards the high-end resolutions, especially after announcing itself as the company that makes the products with the highest quality screens on the market.
A retina display is not incompatible with a consumer laptop. On the contrary. It attracts consumers, maybe even more than professionals. The iPhone and the iPad are both consumer devices, and both feature gorgeous IPS retina displays. I don't see why Apple couldn't put them on the MacBook Air.
Pricing, you may say. There would be no reason for Apple to sell the retina MacBook Pro for a premium if the MacBook Air had a retina display. But that's not true. The MacBook Pro has a faster processor, and is heavier than the MacBook Air (and a redesigned MacBook Air would be even lighter). Plus, with the Haswell processor, battery life of the MacBook Pro could be boosted.
Again, this is just a guess. Apple may leave the retina MacBook Airs for 2014, and my guess is no better than yours. But it seems like all elements for a MacBook Air will be already available in 2013 (Haswell and IGZO displays), so there would be no reason for Apple to delay it, especially when there is the risk of competitors releasing similar products.