I don't NEED an Air either... I guess I will just use my Pentium 4 PC... but then again I may not NEED that
Now you're just being asinine. Just accept the fact that the retina is way overboard for any college student.
I'll make it simple on you. If you're parents are rolling in it and are paying for your laptop, then yes get the retina. It might be one of your last chances to spend money that isn't your's.
If you have to pay for it, or your loans are paying for it, buy the MBA. It is everything you need for all 4 years of college.
PS, if you want extra coding space an external monitor or 2 is significantly better than looking at tiny (but really crisp) text on 1 screen.
How do I know all this? Just finished my degree in physics. Coded in Java, C++, Matlab, Mathematica and Igor. External monitors > Retina for coding. You can easily split the screen up into your console(s), wiki, Pset and facebook

(you all know you had that extra window open all those late nights

)
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I have a BS and MS in CS and it does depend, but I found any 'real' powerful computing was done on systems you could remote into or otherwise done on most PCs including a MB Air.
I would've loved an Air in college.
+1
If you're doing anything actually processor (or GPU) intensive, it will be done on a cluster.
Hence why no college student needs anything greater than 13" MBP (go for the air if you'd rather). Anyone saying otherwise is just trying to convince themselves (or others) so that they feel better about their new toy.