I won't pretend to know about all airlines, but prices are not down on the major airlines that I fly. If anything, the prices are slightly higher -- and aggravated by the recent rules on changing tickets with restricted fares.
The real problem is apparently that lucrative business travelers (who pay full coach fares in excess of $1 per seat mile) are not flying. Some of it is because the economic downturn have caused travel budgets to be cut, but some of it is because the hassle of flying has induced businesses to find alternatives to travel, such as videoconferencing.
Without the full-fare travelers, the airlines are between a rock and a hard place. They can't operate flights at a profit without raising leisure fares above the point that most recreational travelers are willing to pay.