Typhoonpilot is correct.
When USAir, Piedmont & PSA were put together, they had the potential to be a major player. The first mistake they made was parking the BAE-146s, leaving the West Coast, & concentrating on the East Coast. Their hubs, (DCA, BWI, PHL, LGA, PIT, BOS) were now competing with each other (except for CLT). Ed Colodny was smart, but not smart enough. They were operating a "major" airline with a "regional" (Allegheny) mindset.
The second mistake they made was retreating when SWA came into BWI. SWA then expanded along the East Coast, with a 7 cent (vs 12 cent) ASM cost, & started to eat their lunch. They lacked a strategic plan, which resulted in their eventual CH 11 filing.
Now the momentum is lost. They are pulling out of PIT. I'd wager to say that SWA, AirTran & ATA will be in PIT shortly. The Shuttle isn't as lucrative as in the past. (AirTran & SWA fly between BOS, PVD, ISP, BWI, DCA etc..) SWA going into PHL will prove to be the begining of the end. The only thing they have left is the CLT hub, which competes heavily with one of the busiest airports in the world....ATL.
My guess is that they'll end up as a much smaller airline, with only a CLT hub, or they will slowly fade away.