When was the last time you searched the phone book's white pages? If you're like nearly seven out of 10 U.S. adults, the answer is rarely or never, finds a Harris Interactive poll released Thursday.

The survey, commissioned by WhitePages and its Ban the Phone Book initiative, finds that 60% of online adults find contact information online (no surprise there!) and only 22% recycle their phone books. It finds 87% support an opt-in where they would receive the phone book only if requested, up from 81% a year ago.

"It's time to move away from paper and into the 21st century," Alex Algard, CEO of WhitePages, said in announcing the results of the Dec. 7-9, 2010, online survey of 2,257 adults. He said the opt-in movement made "significant headway" in the last year but still faces obstacles. In December, the Maryland Public Service Commission denied Verizon's request to quit the white pages.

Many states still require telephone companies to print and distribute phone books to landline customers, yet since 2007, more have allowed them to stop doing so. Ban the Phone Book estimates that 5 million trees are needed per year to publish the white pages.

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"Sometimes people need to see hard numbers before they re-think the status quo, especially when you're talking about a 132-year-old habit to kick, " Algard said. "We've had 50,000 people sign our petition to Ban the Phone Book who aren't asking to eliminate the phone book altogether, but to just stop automatically delivering it."

Readers: Do you favor an opt-in? How often do you use the phone book?