The relative level of fame of the other actors at the table is essential. Pitt has always been an actor unafraid to make fun of his own vanity for the sake of a role, like as the doofus fitness enthusiast in Burn After Reading, or ugly himself up for a part, like the prophetic mental patient in 12 Monkeys. Here, Soderbergh and Griffin introduce him, still looking boyish and improbably handsome in his late 30s, amidst a rag-tag group of teen actor pin-ups. Basically, it's the next generation of potential Brad Pitts. He's not as young as he used to be. Later in the film, Danny Ocean says to him, "You're cold-decking Teen Beat cover boys," as a way to convince him to do the big casino heist. Rusty is desperate.
What I'm calling the poker scene is actually two separate scenes: In the first, Rusty attempts to teach the actors to play poker but keeps getting derailed by their buffoonery; in the second, Danny appears and the two run a minor con on the teen idols. The first half, which ends with Grace laying out his cards and saying "fellas, all reds," was largely improvised, according to the DVD commentary track with Soderbergh and screenwriter Ted Griffin. Griffin was reportedly cursing Soderbergh's name for "ruining the scene" during filming, but he now thinks it's "one of the best scenes in the movie." Looking back, it's hard to disagree.