I'd suggest a laptop or a netbook, though I might be ignorant as to some of the iPad's abilities.
1) My Univ has a Novell network. By installing Novell I could browse the Uni LAN, internet, and print, all of which I wouldn't have been able to do without Novell.
2) USB. I'm not trying to bash the iPad on this one, but I used USB A LOT on Uni to copy notes to and from friends. Mostly the notes would be on a usb stick.
3) If you use software for your courses, it is more likely to be windows based. Ok, I did engineering, not economics, so I don't know what software you use. We used Matlab, PSpice, Office, LaTeX, Protel Altium, various programming languages and compilers, all of which was easy to do on windows. I've switched over to linux postgrad, and found that while I could find alternatives for almost anything, it made life much more complicated. I could never find a proper PCB layout tool for linux, though.
On the other hand - the coolness factor of the iPad is much higher! ;-)