Cisco Adler, Lydia Hearst, Other Celebrities Party in Vegas

Las Vegas was saturated with tipsy celebrities celebrating the anniversary of the popular Tao nightclub over the weekend, reports the New York Post.

Leading the way? Cisco Adler and Lydia Hearst, his new girlfriend. The pair was spotted cuddling in the VIP room, while Lydia Hearst's ex-beau, actor Justin Bartha, "looked on" from a table nearby. Ah, that scandalous Cisco Adler.

With zero talent and not much in the way of looks, Cisco Adler sure manages to bag a lot of hot, rich girls. And for that you have to take your hat off to him.

Cisco Adler, Lydia Hearst... and some other hot chick.

Meanwhile, stars such as Emmy Rossum, Gabrielle Union, Haylie Duff, Jeremy Piven, Katharine McPhee and Rosario Dawson were seen partying at Tao.

At the nearby Palms Casino Resort, Maroon 5 played their last show on their North America tour for an audience including Avril Lavigne, Rumer Willis, Brooke Burns, Sara Ramirez and Saturday Night Live's Seth Meyers.

Sarah Silverman's party for her boyfriend, Jimmy Kimmel, in honor of his 40th birthday at the Palms was a more intimate affair, with Adam Carolla, Jeffrey Ross, Carson Daly and Huey Lewis on hand to mark the milestone.