I finally used Priceline.com for an airline ticket. I needed to go from PHX-LAX with a six-day advance purchase. I bid $50 the first time and $60 the second time. My $60 bid for travel to either LAX or BUR was accepted for travel on America West Airlines. The total price paid was $75.50.

I received first class upgrades on both flights, as well as Continental OnePass miles (including Elite bonuses). Also, I was able to change my return flight from 12PM to 8PM without any problem or charge (I made the change on the day of departure). It was a good experience, although I probably won't use Priceline again (unless I have less than 7 days advance purchase).