"The Simpsons": 500 episodes, still going strong "The Simpsons" is celebrating a major milestone this weekend, airing its 500th episode. The cultural phenomenon is the longest-running comedy series in U.S. TV history, and it's on TV somewhere in the world, every half-hour of every single day. In the real world, Bart Simpson would be in his 30's by now. Instead, he remains a 10-year-old troublemaker. As for Homer, in 23 years, he hasn't changed his signature grumble. Marge, Lisa and Maggie are still the same, too, but somehow, the show still manages to stay fresh. (Charlie Rose was given a jacket by the producers of "The Simpsons" after appearing on the show. Watch him wear it with pride in the video below.) The show's writers, says Hollywood Reporter Senior Editor Stacey Wilson, "week after week are managing to find satire and new ways of kind of lambasting American culture. And the fact that the jokes are coming through the mouths of little yellow people gives them a lot of license to just be totally absurd. Pictures: 50 greatest TV characters Over the course of all those episodes, the show's characters have become, well, larger than life. They're at the heart of a billion dollar merchandising empire that includes a ride at Universal Studios Hollywood. Over 23 seasons, those who make the show have been on quite a ride themselves. "Simpsons" creator Matt Groening says, "We have writers who actually grew up watching the show. ... I think 'The Simpsons' is like a cavalcade of different comedy styles. There's very silly, 'Three Stooges'-style humor, there's puns, there's slapstick, there's silent comedy-type jokes. ... We rip off jokes from everywhere! Of course, not everybody has always laughed. There's been criticism that Bart is a terrible role model for children. The show still courts controversy. Its guest star on Sunday's 500th episode is WikiLeaks founder Julian Assange. Over the years, it seems almost everybody famous has been on at least one episode of "The Simpsons." Groening says. We've had Kirk Douglas, Bob Hope, Johnny Carson, George Harrison, Ringo Starr, Paul McCartney, and Keith Richards, Mick Jagger. Also, a certain TV interviewer known for his sophisticated style: Charlie Rose. With contracts to keep the show running for two more years, 'The Simpsons" will top a record it already holds as the longest-running situation comedy ever on TV. To see John Blackstone's report, click on the video in the player at the top of this story.