Aside from the CG, your field of study doesnt really matter...It's your grades and everything else in between.
I've met guys who have had Masters Degrees in Aeronautical Science, however, i've also met guys who have had degrees in English and Exercise Science.
If I were you, I would get a non aviation degree. What if Military Aviation doesnt work out for you? Okay, so you go civillian. What if another 9/11 happens, and the industry goes to hell again? Wouldn't it be nice to know you can get a salary paying job in another field? lol.
Just get good grades.