It's possible to make an 11:40 flight, although it might be tight. As Shanghia 100 noted above, stop by the pursers' desk during the cruise to ask for early disembarkation, and have your ticket with you. Then, when you get your tags for disembarkation, make certain they are the right ones for early departures.
When leaving the pier, take a taxi. Do not wait for any shuttles (that includes cruise line transportation) as they tend to wait for the vehicle to fill up.
At the airport, if you encounter long lines, mention your flight time to one of the airline employees and you may get moved ahead in line. This is for both checking your luggage and security. Every time I've flown in the past couple of months, I've always seen people allowed to move ahead in the security line if their flight was about to leave.
Mamaza, if the 11:40 flight is a little too close for comfort, you can ask AA if there are any later flights available. If so, they should switch you at no charge to you. This happened to us last year (different airline, though) -- and it worked to our advantage as we ended up with a non-stop flight, something we didn't have before.