About two-thirds, or 63 percent, of social networking site (SNS) users questioned in the Pew Research Center poll said they had deleted people from their "friends" lists, up from 56 percent in 2009.

Another 44 percent said they had deleted comments that others have made on their profiles, up from 36 percent two years before.

Users also have become more likely to remove their names from photos that were tagged to identify them. Thirty-seven percent of profile owners have done that, up from 30 percent in 2009, the survey showed.

"Over time, as social networking sites have become a mainstream communications channel in everyday life, profile owners have become more active managers of their profiles and the content that is posted by others in their networks," the report said.

The Pew report also touches on the privacy settings people use for their SNS profiles. The issue of online privacy has drawn increasing concerns from consumers, and the Obama administration has called for a "privacy bill of rights" that would give users more control over their data.

Fifty-eight percent of those surveyed said their main profile was set to be private so that only friends can see it.

Another 19 percent said they had set their profile to partially private so that friends of friends can see it. Only 20 percent have made their profile completely public.

The report was based on telephone survey of 2,277 adults in April and May 2011 as part of Pew's project on the Internet and American life.

(Reporting By Ian Simpson; Editing by Paul Thomasch)

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