There have been a number of complaints about the non-airline sites. There appears to be a 30 min or so lag between inventory/price adjustments at the airline site, and one of the Orbitz/Itn/etc sites. I think somewhere in the caviets, they request a significient time delay(30 min or so) between actual booking payment, and the right to deny ticketing.

There may be a delay between the major airline sites also ( Galileo & Amadus & whatever) They do not talk to each other very well, to listen to the people at the airlines.

The disclamer on Orbitz denies everything, and is so long, I could not find anything in it where they actually take any responsibility.