No matter what department, I guarantee that there will not be over 40 students in your class. For me, this is one of the most important aspects of my education; I love that my professors know my name and that we can have great discussions in office hours. Many of them have become like friends.
The rigorousness of your academic life will mostly depend upon the department and the individual professor, but generally speaking, the communications department is super easy and the science departments are much harder. Our business school is one of the top in the nation and it's really geared toward getting a job. In this economy, that seems to be extremely important.
Oh, and then there's me. I'm a philosophy major and a political science major - both of which are not directed at finding a job. Of course, I think these are the best majors anyone could possibly pick and I'm completely obsessed with both departments. Not only are they challenging, but we're learning subject-matter that's applicable to today's political situations. I can't say enough about how much I've loved these departments! My favorite class is called Philosophy and Freud and we learn just what it sounds like - the philosophy of Sigmund Freud. My professor is absolutely amazing, brilliant, and passionate about this topic. Our class is filled with people who want to learn more and are sincerely interested in the subject-matter. We've actually become pretty close as a class because there are only 25 people enrolled.
Generally speaking, I think most students care about their grades. You'll see a lot of class participation and many people in the library, especially during midterms and finals. Students seem pretty competitive and want to earn a good grade. Unfortunately, it doesn't seem like most outside-of-class discussion focuses on school related subjects. We have other things to talk about, like Kim Kardashian's failed marriage.
The last thing that I'll mention about USD's academics is its core curriculum requirements. In order to graduate, you must take a writing class, math competency, three philosophy classes, three semesters of a language, three theology classes, one history class, one literature class, one fine arts class, two science classes, two social sciences, and one diversity class. Taken together, I think the students that graduate from our university are well-rounded and at least basically understand general concepts in different fields. I love that these requirements reach into different departments and give exposure to every subject.