Friday

Caught in the Act!

10/26/2007 at 06:00 PM EDT

• Mary-Kate Olsen, hitting up David Yurman, a jewelry store on Rodeo Drive where she admired a handful of rings. Meanwhile, sister Ashley was also out for the day before heading to Frederick's of Hollywood's spring fashion show at the Hollywood Palladium. The young fashionista hid away in private VIP area with Rashida Jones and others.

• Another Frederick's of Hollywood attendee, Jessica Simpson and "mane man" Ken Paves (plus some friends) hit up Hollywood's Tropicana Bar at the Hollywood Roosevelt Hotel, where they partied early into the morning. The singer sipped on a mixed drink as she stood by her reserved booth, chatting and laughing with her posse. Paves kept his arm wrapped around her the whole time.

• With his music videos showing on a flatscreen, Jermaine Dupri brought his book release promo tour – and fiancée Janet Jackson – westward. (The pair feted Dupri's literary efforts at Marquee in New York earlier in the month.) At the chic soiree celebrating Young, Rich and Dangerous: The Making of a Music Mogul at Los Angeles's Pacific Design Center, the couple held court on VIP couches where they received their guests. Among the partygoers: Melanie Brown, her husband, Stephen Belafonte and Travis Barker and Shanna Moakler. While he was promoting his book, Dupri paid plenty of attention to Jackson, who whispered in his ear as they watched something on a handheld screen.

• Ryan Gosling, joining a game of pool at the Rose Bar inside New York's tony Gramercy Park Hotel. Sporting a red flannel shirt, black cap and scruff, the actor, in good spirits, asked a man if he could team up against him with a female friend.

Sheryl Crow and Philip Seymour Hoffman

Marion Curtis / Startraks

• Also at the Gramercy Park Hotel: Sheryl Crow, sharing a laugh with Philip Seymour Hoffman during a private rooftop bash after the Cinema Society screening of his latest movie, Before the Devil Knows You're Dead. "It was a great night," a source tells us of the star-studded affair. Spotted at the party: Marisa Tomei, hanging out with a very handsome, mustachioed man and "having a good time," a partygoer says. Doing double duty himself, a diligent Ethan Hawke left the screening to run a rehearsal for Things We Want, the off-Broadway play he's directing. But he still had energy to party, popping up at the Gramercy later in the night. And a glowing, pregnant Juliana Marguliesshowed off her baby bump – and spent time chatting with Bebe Neuwirth.

• By K.C. BAKER, JED DREBEN, SCOTT HUVER and LESLEY MESSER

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