The study of the transportation, distribution and logistics industry measured Web site usability in several ways, including how willing companies are to respond to specific questions, whether a site can be trusted with users' personal data and how easy a site is to navigate and access.

"Transportation companies continue to improve because the Web has become too critical to their business to mess with," said Terry Golesworthy, president of The Customer Respect Group. "They've understood the concerns that were raised before, so their e-mail responsiveness has gone up. They've also tightened up on their privacy policies."

The transportation industry as a whole scored 6.7 out of 10 in terms of respecting customers' personal information, according to the firm's Online Customer Respect Study.

In the area of transparency, which measures the clarity of a company's privacy policies, the transportation industry average was 6, according to the report. Among the findings supporting that score: None of the transportation companies shares data with third parties, and 38 percent of them have adopted "opt-in" rather than "opt-out" policies for reusing personal data for ongoing marketing. Last year, just 28 percent of the companies studied had opt-in policies, according to the survey.

The industry scored an average of 5.6 in terms of communicating with their customers online. The Customer Respect Group found that 76 percent of the companies replied to all inquiries, with 35 percent of those replies arriving within four hours. Twenty-nine percent of the companies consistently sent helpful replies within 24 hours, according to the survey.