Wanted to add that there was a blurb on these fares on Headline News... apparently Flyertalk mileage runners have arrived. They included the statement "USAirways will honor these tickets."
Congratulations to all those who picked up the fares. I saw them at the tail end and was not able to get it to price out on any dates in the few minutes I tried before I decided I don't really want more USAirways or United miles anyway..