Jerry Seinfeld A Post-Sitcom Flop?

In writing a nice profile of "Sex and the City's" Cynthia Nixon, the New York Times makes an odd assertion, referring to "the lackluster follow-up careers of the entire cast of "Seinfeld." That would be fine if they were talking about the secondary characters, but surely that doesn't apply to Jerry Seinfeld himself. He's released an acclaimed documentary film about his standup, done an HBO special that scored hugely in the ratings, his every appearance on late night talk shows is a smashing success, he's gone on tour to sold out houses whenever he wants and even his TV commercials (notably the witty Superman riffs for American Express) have been garlanded with attention. Seinfeld's been too smart to do another sitcom (at least, so soon) and he's never tried to have a movie career, but no one could call his work since "Seinfeld" anything other than a smashing success.