The report analyzed the Web sites of the largest 100 companies as defined by Fortune magazine in April. The companies received an average score of 5.7 on a 10-point scale that measured Web site usability in several ways, including how willing the companies are to respond to specific questions, whether a site can be trusted with users' personal data, and general navigation and accessibility.

"This study is a benchmark of how the largest companies treat and respect the online customer, and practices and policies established in this study are often duplicated and copied in smaller enterprises," said Terry Golesworthy, president of The Customer Respect Group.

The highest-rated sites were Intel Corp., Sears, Roebuck & Co., Hewlett-Packard Co., Medco and The Procter & Gamble Co., all of which received excellent ratings. The most improved was Procter & Gamble, which went from 64th place the previous year to fifth place.

"The Fortune 100 sites have tended to be more of an infomercial nature, but this year they've caught up with the data collection that we've seen in other industries, like travel and retail," said Golesworthy. "So a lot more data [is] being collected -- not just the required data but a lot more marketing-type data, including demographics and what customers are interested in, with a lot more marketing back to those customers."

Even so, the amount of data that is being shared outside those organizations has gone down dramatically, Golesworthy said.