Why is Spiderman Better than Superman, or Vice Versa?

Your thoughts, please :) I'm in a debate tournament at my school, and for some reason, that's the topic I'm lined up for tomorrow. I'm not too familiar with Superman, so any insights would be useful (and probably entertaining, too)
Update: Oh, I think I'm literally supposed to be debating about the characters themselves (their powers, their "personalities, etc), rather than the movies. Thoguh either/or probably works.
Update 2: Wow, great responses so far! My debate was moved to next week, so please keep them coming!
14 answers 14