I bought my kindle for leisure reading and loved it. I downloaded lots of free classics. As a graduate student in Astrophysics, it didn't occur to me to use my kindle for school. I tried to send a few journal articles to my kindle, but the formatting was horrible, to many greek letters and equations. Physics textbooks wouldn't work as ebooks, since they are so quantitative.
Recently, I have started a transition to a graduate program in environmental studies. I was surprised to find that almost all of my textbooks for my new classes were offered on the kindle. Instead of lugging around 10 books next semester, I can just take my lightweight kindle. Also, I can keep all of notes in one place and easily transfer them to a word document.
Also, I've found that I read much faster on my kindle, my eyes don't get tired, and it's much easier to pick up and read for short periods of time. I think the kindle could be a great tool for college students who need to get a lot of reading done. I've started this blog to keep a lookout for great textbooks and educational reading available on the kindle. I hope that this will be useful for students, professors, and everyone who want to keep learning.