EXPECTING: Press representatives for former Clinton adviser-turned-ABC news analyst GEORGE STEPHANOPOULOS, 40, and actress wife ALEXANDRA WENTWORTH (who wed in December 2001 in New York City) have confirmed to PEOPLE that the happy couple is expecting a baby in September. No word yet on whether it's a boy or girl. And in other infant news, British supermodel KATE MOSS, 28, famous for her waif-look Calvin Klein ads, is pregnant with a baby due in October, reports Reuters. Moss, who once dated actor Johnny Depp, has been in a relationship with the father of the baby, 30-year-old publisher JEFFERSON HACK, for the past 15 months. . . . CANCELLED: Madonna fans hoping to snag tickets for her London stage debut in "Up for Grabs" this May will have less performances to choose from as the singer's recording schedule has forced her to cancel all matinees, reports Reuters. The star, 43, who plays an ambitious art dealer in the comedy, is expect to begin a 10-week run at the Wyndham's Theater in the West End on May 23. "We completely understand that Madonna has daytime recording commitments that cannot be rescheduled. As a result, we are determined to accommodate all matinee ticket holders," producer Sonia Friedman said in a statement, according to Reuters. Matinee ticket holders have the option of exchanging their seats for a nighttime performance or receiving a refund, Reuters reports. . . .ARRIVED: 'N Sync singer Lance Bass, 22, landed in Moscow today to undergo physical tests in hopes of becoming the first entertainer in space, reports Reuters. Bass began exploring his options after learning about businessman Dennis Tito, who paid a reported $20 million for a ticket to the International Space Station on a Russian rocket last year, the news service reports. The singer told Reuters that going into space would fulfill his childhood dream. . . . EXITING: Julia Louis-Dreyfus's new comedy "Watching Ellie" will be pulled from the NBC schedule after April 2's episode and replaced with episodes of "Will & Grace," reports Variety. NBC execs insist that the switch has nothing to do with ratings and that new episodes of "Watching Ellie" will premiere in the fall. . . . SUED: Action star Steven Seagal, 50, is being accused by his former business partner, producer Julius R. Nasso, of backing out of a contract to act in four films on the advice of his spiritual advisor, reports the Associated Press. Nasso is suing Seagal for $60 million, claiming that Seagal was persuaded to dodge his commitments on the orders of Mukara, Seagal's Buddhist guru.