Over the weekend, American Airlines quietly released new functionality on AA.com which simplifies mileage redemption and allows one-way award travel. This may not seem all that huge, but AA is the first US major carrier to allow customers to redeem half the number of miles for a one-way ticket.
In the past, if a consumer wanted a simple one-way ticket, they were required to redeem the full amount of miles required for a round-trip. For example, a one way ticket from JFK to LAX now "costs" 12,500 miles or half of the 25,000 miles required for a roundtrip "MileSAAver" award in coach.
Consumers can also now book a coach ticket in one direction and first class in the other - handy if award seats are only available in first one way and coach the other. Also nice in this case because the first class award seat is 25,000 miles one way - the same amount as the "double mileage" often required for a seat in coach. We'll take a big seat any day!
It also makes combining miles and paid tickets an interesting proposition, especially in today's world where many airfares are simple one-way tickets. For example, if you found a great fare to LAX from JFK for say $129 but the return was very expensive, you might look at buying a ticket one way (and earning more miles!) and using miles for the return.
Southwest, JetBlue, and AirTran all offer one-way awards today but AA is the first of the majors. Many international carriers also offer the option including fellow AA oneworld partners British Airways and Cathay Pacific along with Air France/KLM.