I bought an Amtrak ticket to go to New York in January. I'm using a Flyer Talk event as an excuse for theatre going and bought a ticket to see "Finian's Rainbow."
Within hours of buying the ticket, I got an invitation to another party in New York. Which I could make it to if I could change the train ticket up to a few hours earlier. I did have to go through a bit of a phone tree to get to an agent (you can cancel, but not do changes on-line) but once I did, it was a breeze. Not only did the Amtrak agent make the change easily and quickly, but she was cheerful and friendly about it. And, not that it really mattered, going up earlier also makes it about 20 bucks cheaper.