Pros
You will learn new technologies quickly. Orbitz infrastructure fields a large number of requests. The amount of knowledge you will gain on scaling large system is immense. The people you will meet there are friendly and smart. Free pop, oatmeal, foosball, air hockey and multiple annual parties make for nice benefits. The pay tends to be generous and vacation time is quite good. Work schedules are loosely defined which allows for some nice flexibility.
Cons
While working at Orbitz, you will be constantly reminded that you are the #2 company in the space. This tends to be frustrating as it seems like all the right people are in position to take the #1 spot. The culture is ill defined and generally negative, likely a result of too quick growth. Most engineers will be responsible to support the site via pager duty.