Among the concerns about cloud computing: 80 percent of respondents said they'd be very concerned if a vendor used their photos and other information in marketing campaigns. Another 68 percent said they'd be very concerned if the vendor used their personal information stored in the cloud to deliver personalized ads to them and 63 percent said they'd be very concerned if the vendor kept their data after they tried to delete it.

Asked why they use cloud computing services, 51 percent said convenience was the major reason. Another 41 percent said the major factor was being able to access their information from multiple computers and devices.

One audience member suggested consumers' growing use of cloud services doesn't match with their concerns about the privacy of their data. Schwartz said consumers would embrace privacy protections if they were made easy to use.

"People are obviously making tradeoffs in privacy when they use these services," added John Horrigan, Pew's associate director for research.

Asked what policy recommendations they'd make to the U.S. government, Nelson and Schwartz suggested a change in government procurement regulations are needed for federal agencies to embrace cloud computing. But questions about data privacy and ownership are also important to address, Schwartz added.

The U.S. government should encourage the free flow of information around the globe, added Dan Burton, senior vice president for global public policy at cloud computing vendor Salesforce.com. The benefits of cloud computing could be hampered by laws that prevent the sharing of data across national borders, he said.

The government should avoid formulating specific policies governing cloud computing, according to Nelson. Government's role should be to ensure competition and allow vendors to work out details, he said.

"I do think government has an almost infinite ability to screw up things when they can't see the future," Nelson said. "We have to have leadership that believes in empowering users and empowering citizens."