You guys we making this so hard for me to decide between a MBA and MBP. Of course I'm typing this on an iPad. I think likely the iPad will get sold when I get the laptop. I love it, but when I get e iPhone 5 with the bigger screen it will fill the roll.
I don't think I'll play too many games on it. My main use will be running unix programs from school (cadence design tool), lots of photo editing, and media watching.
Obviously having a powerful discrete GPU and a faster clock speed on the CPU will help dramatically. Being able to see almost my entire photo at once will be great. However even with my student discount that's 2600 easily after apple care.
The MBA is cheaper lighter, and a bit slower, and a hell of a lot cheaper. I don't want to dump my laptop until applecare expires. It makes sense to me the retina book is way more future proof. But if I'm only using the discrete GPU for photo editing I'm on entirely sure it's worth the premium. The screen rez may though. Am I making any sense?
The MacBook Air is a spectacular laptop. My ex-gf had a C2D 2nd Gen model (same design, old CPU), and it was easily the best laptop I've ever used. And I had a C2D MBP at the time.
IMO, you're taking two differences and blowing them into a huge decision. I'm not saying this will make things easier; but just consider that the two big differences are:
Higher Res screen in the Retina, and a dedicated GPU.
Sure, the processors are faster, and you can get more RAM, and better speakers, blah blah blah. But the Ivy Bridge CPUs, even in the MBA are pretty damn solid. They're not going to struggle too much unless you're really working hard with CAD/Adobe filters/etc. And the 8GB of RAM you can get in the Air is likely more than what 90% of computer users need right now and in the near future.
So, yeah...
Is the higher-res screen and the GPU worth the ~$1K difference to you?
It very well might be! I'm not trying to lean you one way or the other. Just trying to break down the terms for you.
Good luck, man. I know it's rough! I remember spending a couple weeks debating between the black Macbook and whit Macbook when they first came out in... 2006? lol
EDIT: Also, I know this is an unpopular opinion; but I never worry too much about "future proofing." Buy the computer that suits your needs best right now. There are a million and one reasons why you might end up having to buy a new computer in a year or two anyway; and there are a million and one reasons why either the Air or Retina could possibly last you longer than you could have ever dreamed. But at the end of the day, realistically, both are going to start feeling "old and outdated" around the same time, anyway.