Regarding Mileage-based upgrades and waitlisting:

http://www.flyertalk.com/forum/conti...ml#post7374763

It might be good to explain what happens when a waitlisted upgrade clears. The CO FAQ says:

"Upgrade is confirmed at time of reservation if a seat is available. Waitlisted customers are confirmed automatically once a seat becomes available"

Will the passenger get a notification, or is it best to keep checking the status online?

(great FAQ, by the way. Helps me a lot)