I would not suggest going to college on simply an iPad alone without a laptop. I mean, sure you CAN get by; there are some people that don't have their own computers and use the ones on campus libraries, but I think that's a really big inconvenience.
I think now having your own laptop is a must in college, but that's my opinion. I have a MacBook Pro 13" and just recently bought an iPad 2 too, but I could never see my iPad 2 replacing my MacBook and becoming my main computing device.
I do now just use my iPad 2 to type out notes in class, but it's much less accurate than on a laptop. I take it to class because it's lighter, thinner, and I enjoy taking notes on it more than my laptop just because it's fun, but I wouldn't say it's easier. You could get a external keyboard, but then that means you're now carrying two devices, and it defeats the purpose of carrying such a small device.
Also, I don't know how well I'd be able to write a paper on an iPad even with the keyboard. On an iPad you can only be viewing one thing at a time, and that would be the word processor, so it's very difficult if you compare it to a laptop where you can have multiple windows open, even side by side, and you can have your research open in one window while you type in another. Or you can have a dictionary open in a tiny window without having to continuously app-switch, which would be difficult, especially if you're trying to look at one thing while typing something else.
Also even just having my iPad for a little over a month, I've been required to go to certain websites to view material that requires flash, and I've had to open it up on my laptop. You might also come across the need of using certain programs that require you to have a real computer that allows you to download these programs.
Opening up web pages is also much quicker on a laptop. The biggest issue with me right now is that with my computing habits, having much more efficient being able to have more than one window open side by side.
Still love to use my iPad though.
