Nielsen Media Research says the "Late Show With David Letterman" beat the "Tonight Show" last week — the first time in more than three years.
It was Letterman's first win during a full week of all-new broadcasts since December 2005, when Oprah Winfrey was his guest on the CBS late-night show. Letterman was perhaps given a ratings boost from lingering controversy over a wisecrack that targeted the family of Alaska Gov. Sarah Palin.
O'Brien took over "Tonight" from longtime host Jay Leno earlier this month.
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