One Atlanta-based travel agent shifted one set of clients traveling to Europe this fall from an American flight to a Delta flight.

"Price was about the same. American had a slightly better schedule, but I am not looking for headaches and canceled flights are big headaches."

"In our business, it is very hard to recommend something that you know is not certain," wrote the travel agent, who didn't want to be named, in an e-mail. "Any time you have labor disputes and/or financial problems, the dependability factor goes down."