When the follow-up to Jurassic Park (currently titled Lost World) hits theaters next summer, the dinos will be back, but Sam Neill won’t. Instead, look for little-known Vince Vaughn, 26, as a nature photog ensnared in a plot to clone the reptiles. It was Vaughn’s first starring vehicle, Swingers (due Oct. 18 from Miramax), that caught director Steven Spielberg’s attention. Based on Vaughn’s real-life escapades with costar-screenwriter Jon Favreau, Swingers is a comedy about the buddies’ quest for fun and women in the L.A. lounge scene. ”It’s so strange to think, Okay, I’m going to work with Steven Spielberg and Julianne Moore,” says Vaughn. He’d better get used to the idea: Filming begins Sept. 3.