Pros
The benefits package is better than most, particularly if you like to travel. Medical insurance costs are lower than most. In IT, your experience will vary greatly depending on the group you hire in to. Some groups are driven by unrealistic expectations and/or poor management and processes; others have rather advanced processes and effective management. Moving between groups is possible, but not easy. US Airways is always hiring in IT since the IT group is growing rapidly. In IT, the average employee longevity is quite high - people tend to stay there once they hire in.
Cons
In IT, many groups are severely under funded while others have too much cash for their own good. Your experience in IT will depend greatly on the director you report in to - the directors and VPs really set the tone and budget for their areas - not the managers or senior managers you may interview with. Some of the directors are airline people, not IT people, and don't understand IT needs and processes; others are quite advanced in their IT methodologies. Be sure to find out whether the director you will be under "gets" IT. If he doesn't, I would avoid hiring in to that area and find another job. The hiring process can be slow. Even after an offer is extended, plan on 30 days before you actually start work.