I had a return on American on March 10th (BZE-MIA-TPA) and was not charged. The gal at the counter wrote down 40.00 on the ticket, but no funds were collected. Same for my travelling companion. Nice surprise as I thought I had a cheap ticket anyway.
I am going again in April and sometimes wonder if I could be the one singlehandedly driving up those tourist arrival figures (6 times in one year).