I once asked UA if they were coming out with a Mac version of the software. No such luck in getting a positive response. I find the web UA connection too slow for my taste. I like shopping at Easy Sabre for fare codes and then I call an operator. That way I know that there's always a better fare.

I also checked the new AA website with their online reservations system, but found it to be somewhat buggy (both with IE4 and Nav4). I tried booking a ticket to Belo Horizonte, Brazil (CNF) and their response:

"Selected City not served by American Airlines".

And when I called them up- There it is! Belo Horizonte!