"What we found is that the industry in general is doing a lot more cross-marketing internally," he said. "The number of [companies] using a consumer's data internally has gone up. Now, 71 percent of all companies are going to routinely remarket to you whether you say you want them to or not. That's quite a high percentage. [In other industries,] we see that typically in the 40 percent-to-50 percent range."

In addition, the number that share personal data with outside companies including business partners has also gone up to 41 percent from 31 percent, Golesworthy said. "This breaks a trend where we've been seeing this number come down consistently [in other industries] over the past couple of years," he said. "But we've seen the airline and travel industry actually go the other way."

The travel and airline sites rated most trustworthy were those of Expedia, Intercontinental Hotels Group PLC and Southwest Airlines Co., according to the study. The most generally usable sites were those of Royal Caribbean Cruises Ltd., Celebrity Cruise Line and Continental Airlines Inc. The best sites for one-on-one communications were Web-based resellers Cheaptickets.com, Travelocity.com and Orbitz, according to the study.

The highest-scoring company in terms of simplicity was Celebrity Cruise Line with a score of 9.2 compared with the industry average of 6.6, and in the area of attitude, Marriott topped the group with a score of 7.8 compared with the industry average of 5.5. In communication, Cheaptickets.com was first with a score of 8.9 versus 5.5 industrywide; in transparency, Expedia scored highest (8.5 versus 6.3); and in privacy, Southwest Airlines topped the list (8.2 versus 6.0).

Golesworthy said even though 46 percent of customers say that they have no patience for Web sites that are hard to use, hard to navigate, slow to load, difficult to read or hard to find what they're looking for, only 23 percent of travel sites limited their home pages to 150K or less; 57 percent have no site-search capability; and 90 percent of sites do not use resizable pages or resizable text.