If you click around the radio buttons above, the form resets. Orbitz does an AJAX call to reset the form with new HTML. I can select two cities, select my dates... and I just decide to click "Flight + Hotel", Orbitz blows away my form submissions (data loss!) and replaces it with a blank form! Not only is this rude to the user, it's bad for business.
This simple UX gaffe could be worth double digit percentage decrease in revenue for Orbitz over the course of a year. For a company that made over $700 MM, that's could easily be over 9 figures.
This could be solved with an incredibly simple and tiny amount of javascript to remember selected airports and leave/return dates. It could be fixed in less than an hour by a halfways decent hacker.
It's things like this that make me thankful for Hipmunk.