I upgraded from a 13" MBA (July 2012), to the rMBP 13" in November 2012. The 13" rMBP is the machine I was holding out for (as I require portability), and why I did not go for the 15" rMBP. Since my purchase, I have really begun to miss the weight and portability of the MBA. I have heard rumours of a 13" rMBA coming this year, which would be much more preferable for me (as my mobile computing needs are not cpu intensive). Is anyone else in the same situation, torn between wanting a retina display (yes, I'm a display junkie) and the light weight/portability of the air?