Well, I did a complete erase and reinstall. The only things I carried over from the old system were my itunes library and assorted school documents via external backup.
It's been almost a week now (6 days, to be exact) with heavy Airport use, and I haven't seen any problems.
I called Applecare before doing the install to make sure that my problem had a case number, and the person I spoke with seemed to think that bad hardware, specifically bad RAM, would cause more frequent and regular panics. I kind of agree with that. Yes, I had 5 panics, which is too many, but that was over around 7 weeks time. It's very bizarre to me that there was obviously a problem, and yet the problem didn't manifest itself often enough to suggest major issues.
I'm inclined to think that it was in fact problems with the Airport driver (which has recently been updated), but I guess I'll have to wait a little longer before I'm totally satisfied. Thanks to all for your help.