More good news for you. Tri-Rail has been extended to the new MIA transport terminal. So there's no longer a need to wait for a bus shuttle between the last station and the airport. Now you would just exit at the Tri-Rail MIA station, and follow the signs to the Airport Mover -- which will take you to the terminals.
Here's the thread on the subject ->>
http://www.flyertalk.com/forum/flori...l-station.html