I notice most 2000+ Bonnies I see have at least 1 of the 4 taillight bulbs out and mine blew recently for no reason. Is this a common problem?

Pretty common. There is a common short in the wiring and they can go in and out. Mine will sometimes not work for the parking light, but the brake light will work fine. Then all of a sudden it will start working even if I don't change it. I have seen this a couple of times.

I've only changed 2 in the year and a half i've owned the car.