One additional thing for the newbies...

Jumseating is designed first and foremost to get people to and from their domicile, or some other jumpoff point where the company would not be responsible to get you there. If the company is sending you on a trip and you jumpseat to get there (i.e.company travel for company business) you can NOT jumpseat.

Also, it is good manners to allow someone who is going to work the opportunity to get on the flight in front of you if you are going to meet the wife at the condo on the beach.