Q. Using MSN's LiveSearch, I just discovered Farecast and used it to look for airfares departing from San Diego. Do you see these guys as a competitor? I would love an impartial review of this site on your part, especially how it differs from Airfarewatchdog.

A. There are a couple of things to consider: Farecast doesn't include promo code airfares, or fares from Southwest, Allegiant, DirectAir and other airlines that sell fares exclusively on their very own sites.

Another distinction is that you can choose specific travel dates to get Farecast alerts, which is good if your plans are inflexible. But if you're open to traveling on any date, just so long as you're getting the lowest fare, it's not so good. We list the lowest fare irregardless of exact travel dates.