I can get iWork for $71 through the education store on apple.com. I may just go ahead and get it. I can also download Office for Mac from my school for free. If I don't like it or it's too slow, I can always remove it. I have heard lots of good stuff about Keynote.
I don't actually plan on installing Windows on my Mac. If I absolutely need to do something on a Windows computer, I can use my desktop at home. I will eventually replace it, but it's just a year old and is still running pretty good.
As far as documents for school goes, I have had professors who are all over the place on the issue. Some will accept pretty much anything, but those are the ones who are computer savy and know how to open different formats. Right now, I am taking two classes and one will only accept assignments in .doc format, period. If it's not submitted in .doc, you get a 0 on the assignment. Pretty harsh if you ask me! The other said that we can use .doc or RTF. He specifically said no .dotx because he can't open them. Gotta love flexibility! LOL!
Microsoft Office has more features than iWork. Office 2008 is bloated and a huge memory hog, a bad program indeed. And it has some compatibility issues with Office for Windows.
However, if you want the real thing, you've gotta go with Office 2008. Pages does not even support cross-references, which is a basic feature of serious word processing. Excel excels Numbers in almost every way. Keynote is indeed superior to PowerPoint. But then you won't be able to reproduce your presentation in a Windows machine. As I often have to open my presentations in someone's else machine (always a Windows computer), I have to stick with PowerPoint.