After spending 4 days obsessing over this question for 16 hours a day, trawling through countless number of threads on here and other sites, I've finally made up my mind. If you've reached a point where you cannot decide between a retina display or 4 hours of extra battery life, and plan to use your new laptop the same way as I do, then I hope this will help you make up a quicker mind! Starting off, I planned to buy a "travel" laptop so I can produce on the go (web browsing, Skype, document editing). For this reason I needed a laptop with a pretty long battery life. Now, for me, there aren't that many things that matters when it comes to the MBA vs rMBP - They are nearly identical in size (tapered Air doesn't make it smaller) - The weight difference is almost negligible (220g difference) - Processing power is not that important for web browsing and document editing But what do make the difference, are the screen and the battery life. The retina screen vs 4 hours extra battery life was what it ultimately boiled down to. Let's look at the quality of user experience in each case: - Retina display - Superior contrast and text sharpness (you don't miss what you never had, but it is easier to read text off a retina screen, the text is darker and the smallest text is immediately legible) - Longer battery life - Never carry a battery charger in your bag again for a day job The retina display and longer battery life each improves the user experience in a particular way, and while I'd like to have both, you have to choose. OK, so you're like me and you would like to work for a whole day without plugging your laptop in. But let's think for a moment, how long do you actually plan to spend out there before coming back home/hotel? The rMBP has a rated 9 hour battery life, will you actually be working for >9 hours ALL the time? For me I might want to work on my laptop continuously for >9 hours 10% of the time, the other 90% of the time a MBA's battery life doesn't make a difference. I'll look at my schedule for the day and will only take the charger with me if I think I'm gonna need it, which is going to be around 20% of the time. So looking at it like that, the retina display will improve my user experience 100% of the time, whereas the crazy battery life will only benefit me 20% of the time. Ultra high resolution screen is the future, I dunno about you but in 2 years time when all ultrabooks have a full HD+ screen, I'm gonna feel left out if I picked up an Air. Hope this helped you, sorry if it was a bore!