Though Letterman’s been beating Conan in total viewers fairly regularly lately (he did it again last night, with a small assist from Sarah Palin), NBC has proudly pointed out that the Tonight show is still winning among adults 18 to 49, the only demographic advertisers worry about. But now, Letterman’s closing that gap too! Last night he lost to Conan by only about 30 percent among adults (his smallest margin so far), while apparently alienating none of the children ages 0 to17 that have been crucial to his overall ratings victories. [Live Feed/HR]