Since the start of 2010, the highest number of complaints -- 18,196 -- related to damage claims for checked bags, problems for which airlines and the TSA share liability. (It's also the area that experienced the biggest decreases in recent complaint tallies.) In second place, at 10,187, were complaints about treatment of personal property at security checkpoints.

The mood toward the TSA isn't good, but it was worse in late 2010, when the TSA began to deploy full-body scanners and pat-downs in airports, said National Geographic Traveler's ombudsman and consumer advocate, Christopher Elliott.