I was about to close my AA advantage mastercard when I asked the operator if there were any promotions so I could get miles for keeping the card. Then he told me that I could switch to a new offer.

This is how is works. You should call a card a specialist and tell them you would like to switch your card to a new offer. I think they have to "register" you for this is in your account notes. I was read a diclaimer saying I have 10 days to fax them the offer or 20 days by mail. So I faxed a 30,000 miles offer for the AA mastercard with no annual fee and just called 2 days ago and it was approved. This is a little known secret. Sometimes they are declined but make sure your account is in good standing before you try to recycle your plastic. I hope to hear some little known secrets from you flyer talkers as well. I am going to try this with some other credit cards also.
I tried to do the same deal with my AA business card but the guy on the phone said the same thing was not available.

Also the rep on the phone gave me is name and AM number to write on the fax i.e attention Mark AM *****
I wish you luck and please recycle that plastic for free miles
peace