Yeah, better late than never. The Canadians have been doing this for some years. The Japanese for most of this decade, and it was invented in Finland in 2001, but yes, American Airlines is now finding mobile phone based check-in the convenience for travellers and the cost-savings method for the airline, and is expanding its mobile check-in to three more airports (Las Vegas, Atlanta, Minneapolis). Meanwhile, back where it started, in Finland Finnair reports on some of its busiest business-passenger routes more than half of passengers now use the service. Yes, this is one of those magical services we can't wait for them to become ubiquitous.