Pros
The money is decent and the hours are pretty flexible (provided you are part-time). The informal atmosphere is comfortable and the management is totally adequate. They were awesome about working around my school schedule while I was finishing up my degree and pulling crazy hours in the lab. Coworkers are very cool, even though we all stress out and scream at each other during the shift, it's all water under the bridge at the end of the day.
Cons
This is a very stressful job. Some customers (less than 5% probably) are certifiably insane. They will let you know that you are a lowly server, and fail at life. If a customer is rude to you, you just have to suck it up. This is a skill I have developed over the years. I've seen some awesome servers get fired because they lost focus and snapped at a customer. Unfortunately, a great number of restaurant workers are full blown alcoholics and/or drug addicts. Not that they are scary or anything, but if you choose to abstain from drugs, are a recovering addict, or consider yourself to be impressionable, then this is not the line of work you should be in.