I do know that if you book on a Thursday or Fridays the fares are usually more expensive and usually go down late Sunday/early Monday.
USAir usually increase their fares after 10:30/11:00am (sometimes)
Delta has COMPLETELY lost their minds with airfare between 800 - over 1000!!!
I am going to be booking Airtran since that is the only direct non-stop leaving from the Washington, DC area. (I refuse to change flights this time!!!) BUT....BUT if the fare is like $300 cheaper on American or USAir I will just suck up the switching flight fasaco!!!!