I got the USAir card too. I am sitting on 2 free RT worth of miles right now. Hoping that's even more when the transition happens. Since we moved SW of Philly, BWI is only about 15 miles further than PHL. South West just started non-stop flights out of BWI. I also have their card. Much cheaper, and much better mileage program.

We used our miles from SW on AirTran over Jan. Not as nice as USAir and you cant use the kiosk to check in at MoBay, but the price difference for the flights was about 100 each ticket.