So if I get an FRS radio, I'll be able to hear others on a CB radio? Or is it a different system?
FRS and CB are two separate systems, so one won't receive from or transmit to the other. We generally use FRS, some other clubs use CB more.
The FRS radios are fairly inexpensive, every vehicle on a run should have one. They are the primary mode of communication between vehicles for us. We mention CB as an alternate, but not everyone has one, and from what I've seen they are not used much on our runs. If you only have CB someone would have to relay the messages to you.
To save Paul the trouble of typing it: those of us who have not yet gotten HAM licenses (myself included) really should do that. Much better range, benefits, etc.