Welcome to the Smart Set. Every morning we bring you the gossip coverage, filtered. Today: Justin Bieber takes his paternity test, Diddy isn't changing his name, and the updated power structure at Conde Nast.

  • Sylvester Stallone is joining forces with current heavyweight champions Vitali and Wladimir Klitschko to produce Rocky: the Musical. The script is being written by "broadway veteran" Thomas Meehan, who worked on the film version of The Producers, and will reteam the lyricists and composer from Ragtime. On the whole, the show's cost is being budgeted at close to $15 million. They also don't have their young pugilist cast yet, though when he's set, the Klitschko's are going to get him into fighting shape. The show is scheduled to make its world debut in Hamburg next November. [The Hollywood Reporter]
  • Nantucket's pilots are going to be grounded for five days this, and it's all Joe Biden's fault. Monday evening, the FAA "closed the skies over the island" so the second family "can again spend their Thanksgiving hols on the Little Rock." To be fair, it's not like they're a bunch of Joey-and-Jill come latelys. The Biden have been celebrating Thanksgiving on Nantucket for "three decades." According to scuttlebutt, the word is "wife Jill and daughter Ashley are spending the weekend in a private home in the Capaum Pond area, a historical section said to be the site of the first settlement on Nantucket." [Inside Track]
  • During an interview with Sean Hannity yesterday, Mitt Romney said it would be "presumptuous" for him to begin putting together a list of possible vice presidential picks. Then he said that he has such a list and that's about 15 names long, and New Hampshire Sen. Kelly Ayotte is on it. [Playbook]
  • 84-year-old Conde Nast chairman S.I. Newhouse's influence has apparently quietly declined at the company over the last two year, with the company's board of directors now making many of the decisions that used to fall to Newhouse. One Conde Nast source describes Newhouse's current post as a kind of "emeritus" position. [Forbes]
  • Justin Bieber formally provided a sample of his DNA on Friday to establish whether he's the father of Mariah Yeater's baby. Yeater's lawyers were adamant that the test needed to be conducted under "very controlled circumstances," because of threats against their client. Yeater lawyer Jeffrey Leving "even reserved the right to re-file the case if the two sides can’t broker a mutually acceptable test," but they did, because Bieber took the test. [New York Daily News]
  • Alleged-exes Jennifer Lopez and Marc Anthony apparently found out breaking up is like knocking over a coke machine when they were in the same hotel to film their reality show Q'Viva! The Chosen! in Puerto Rico earlier this month. Evidence that they were canoodling consists of Anthony picking up Lopez at the airport and the fact Anthony "never stayed in his hotel room" (maybe it was someone else's hotel room?) Either way, a friend says the Lopez/Anthony backslide is "inevitable." Explains the source: "Marc has got this hold over her." The duo announced they were separating back in July. [Us Weekly]
  • A rep for Sean Combs insists the rapper has no intention of changing his stage name from "Diddy" back to "Puffy," though the "the cocktail chatter at the Los Angeles party for Raphael Mazzucco’s “Culo” Photo Art Book launch at the Sunset Marquis" suggested otherwise. Diddy could have been there to set things straight, but elected not to go out of respect to rapper Heavy D, whose funeral he attended Friday. [Gatecrasher]
  • A spy says actor Jake Gyllenhaal and noted Georgetown Day School Mighty Hopper Olivia Wilde looked "very cozy" during a recent dinner at Chinatown Brasserie. The two were spotted together at the Chateau Marmont in June, but reps for two actors insisted they were just friends. [Page Six]
  • Katy Perry emphatically denied rumors that she's about to have a baby. Said Perry, on the subject of babies: "Hell no!" [HollyScoop via People]