Through Dec. 15, 2011, American AAdvantage Platinum and Gold elite members will receive complimentary upgrades to first class on American Eagle nonstop flights between New York (JFK) and Nashville, Cleveland, Washington (Reagan), Toronto, Baltimore-Washington, Columbus or Raleigh Durham; New York (LaGuardia) and Atlanta, Cleveland, Columbus, Minneapolis, Nashville, Charlotte, Detroit or Raleigh Durham and between Los Angeles and Albuquerque, Houston, Phoenix, Denver, San Diego or Oklahoma City.

Bottom line: Unlike US Airways, United and Delta, American offers unlimited complimentary upgrades on domestic flights from all fare classes to its highest-level Executive Platinum members only. AAdvantage Platinum and Gold members earn four 500-mile upgrades for every 10,000 qualifying miles flown which can be used to upgrade to the next class of service. For a limited time, Platinum and Gold members will receive unlimited complimentary upgrades from any published fare on the select routes without having to use their 500-mile upgrades. Any traveling companions, however, are not eligible for the complimentary upgrades.