At the moment, I don't think the iPad and the entire infrastructure is developed enough to jump off with a iPad only. The issues with printing and files will be mostly solved with OS4. However you still do need something to sync files with that is secure to you. This is the biggest problem with the pad as; my only computer option. Perhaps this will be solved, eventually with a 'Cloud' computing option, but it is still a future thing. Many of the other are moot, as the schools almost universally maintain computer centers that allow students to do almost all there work there.
If you examine University of Arizona for example, which is extremely advanced from an IT standpoint. They prefer you use a Mac for a start. Some classes are set up to use the features of either an iPod Touch or iPhone to engage interactive features of multimedia presentation. Many professors will accept papers and assignments on email. Notes are by in large put up on the web as are videos of many lectures of large classes. WiFi coverage of the campus is 100%. However, there is still a need to store and sync your pad and there is the holdout professor or class, due to physical need, uses paper printouts.
If you have to pay to print in the campus computer center, you will very quickly outstrip any saving you may have effected. There are programs, depending on your major, that need to run on a full fledged computer. You can go to the computer center to do that, but you end up with so many workarounds to achieve a iPad only life, it makes you the slave to the pad. Remember, a computer is supposed to be a labor saving tool, not a lifestyle statement. So like a can opener, you are not really wanting to go out of your way to use it to open cans.
Any monetary saving you may see from the iPad, would be quickly outstripped by the accessories you would ultimately need to purchase. Recent articles point out that nearly 20% of the profit coming in from the iPad is accessories. Just like Lucas putting Teddy Bears in Star Wars to sell toys, Apple made the pad need (or perceived to need) a few extra items. It really improves the bottom line.
Go on Craigslist and get a used MacBook. You can easily get one for under $600 and after two months in your backpack, they all look abused. While this will draw hoots and howls from the winworld, the Mac and its orbiting peripherals is very firmly ingrained in most campuses across the country. Quite frankly a two year old MacBook is better than anything you can get from Dell. Agreed they are cheaper, but even with the improvements made in Windows 7, it is still, Windows. You don't need to make fun of it or anything, it speaks for itself.