I ask because (1) the airline websites tend to be _really_ slow and (2) they tend not to find the cheapest/best flights - an ITA search can often beat them.
1) Part of our reason for using Node+Socket.IO is to deal with the problem of having a bunch of different sources returning data over a wide spread of time.
2) You'd be surprised about the airline sites. While they don't necessarily have the widest variety of good fares, airline will often reserve their cheapest fares for their own sites (called Last Seat Availability).