American Airlines latest to tweak frequent flyer program; 110 million affected.

Newly-merged American Airlines and US Airways are making big changes to their frequent flyer programs, parent company American Airlines Group announced Tuesday. Following in the steps of several other major US carriers over the past year or so, the company will reduce the number of points needed for certain flights but increase them for others. Like Delta and United earlier this year, it will also introduce a system of tiered point-redemption categories, making the process of redeeming points for a ticket more complex. [ABSTRACT FROM AUTHOR]