Wednesday

Caught in the Act!

09/24/2008 at 06:00 AM EDT

• Ashley Olsen, joining beau Justin Bartha on the Las Vegas set of his new movie, The Hangover as it filmed on the roof of Caesars Palace. "She was cute, laughing and giggling throughout," a source says. "She was wearing a headset and listening to the whole production while Justin was shooting." Between takes, the two interacted, and Bartha would touch her face tenderly. According to the source, he referred to Olsen as his "girlfriend." While in Sin City, the two stayed in a suite in the Augustus Tower at Caesars Palace, and Olsen relaxed in the spa while Bartha continued filming.

• Ellen DeGeneres and wife Portia de Rossi, joining a small group for a celebratory dinner on the patio of West Hollywood's Il Sole. "They're so in love," an onlooker tells us. "Doting Ellen was seen feeding Portia a bite of tiramisu for dessert." Nearby, Kate Bosworth shared a girls night out with a friend, splitting the Dover sole and bellinis.

• New Hollywood lounge Bardot opened its doors to friends for a low-key evening of old school tunes spun by Ryan Gosling and a live band and burlesque show. The actor, looking dapper in black pants and a white button-down shirt, played tunes from an elevated deejay booth while guests enjoyed small plates of American bistro-styled food. A casual Catherine Keener chatted with friends near her table, while Brothers & Sisters' Emily VanCamp sipped wine over dinner with a pal. Gosling seemed confident with his deejay gig, and later checked out the live band in the neighboring room. The night ended with more tunes from Gosling, including '80s favorites like "Walk Like an Egyptian."

• Vince Vaughn had the perfect dinner date while visiting his hometown of Chicago – his mother! The actor stepped out to Gibson's Steakhouse for a meal with his mom while in town to support the Chicago Cubs.

• How I Met Your Mother's Alyson Hannigan and hubby Alexis Denisof, sharing lunch at casual eatery Blue Plate in Santa Monica. The two sat by the window, talking over lunch. "They kept to themselves and were quiet," says an onlooker. After they paid, the pair walked out holding hands and smiling and headed down trendy Montana Avenue.

• By JENNIFER GARCIA, MARK GRAY, MARY MARGARET and LESLEY MESSER

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