Mark Cuban is diving headfirst into the AI video boom — and he says it's just for "fun." The billionaire investor and former "Shark Tank" star said on Thursday that his "Cameos are open" on OpenAI's video-generation platform, Sora — appearing to be one of the first major public figures to openly experiment with the tool. In posts on both X and Bluesky, Cuban told followers: "For those of you on Sora , my Cameos are open. Have at it." In a separate X post, he added that users can join the