Just got back from my local Apple Store. I was there checking out the 15" rMBP. A lady, who was looking for something light to replace her old 13" MBP, was talking to an Apple salesman next to me. Based on her needs, a 13" MBA would have been perfect for her. However, he successfully upsold her on a 13" rMBP (she couldn't tell the different in displays, even after he tried comparing them a few times). The guy explained to her that having a discreet GPU was like two processors working at the same time, but then directed her to a 13" rMBP without a discrete GPU. She was very confused. The guy just kept throwing out nonsense that was technically incorrect. He never once mentioned the battery life advantage of the new MBA. I decided not to step in because it wasn't any of my business, however, I almost did! I wanted to tell her that new Haswell rMBPs are right around the corner, and a 13" rMBP would benefit greatly from an increase in graphics performance. I also wanted to mention the battery life advantage of the MBA, since that's something she would notice before the retina display. But, at the end of the day, she was leaving with a perfectly fine machine and probably felt good about it. What would you have done?