Worst Ratings Summer Ever for Jay Leno 'Tonight' host still beating Letterman, though By Evann Gastaldo, Newser Staff Posted Sep 3, 2010 10:59 AM CDT 13 comments Comments Entertainer Jay Leno performs his standup comedy act using topical issues at the Beau Rivage Resort & Casino in Biloxi, Miss., Saturday, Aug. 21, 2010. (AP Photo/Rogelio V. Solis) (Newser) – Jay Leno is not having a good summer. In fact, he's having his worst summer ever, at least as far as Tonight Show ratings are concerned. This summer is actually the lowest-rated ever for the show—and even Conan O'Brien pulled in better numbers for the coveted 18-49 demographic last year than Leno is doing this year. Still, with an average of 3.8 million viewers, he's beating David Letterman, according to the Hollywood Reporter.