There was one thing Sam Worthington didn’t admit when he signed on for “Man on a Ledge” — his fear of heights. He’s seen hanging on a precipice at Midtown’s Roosevelt Hotel, 21 stories up, and was harnessed on the ledge for weeks. The thriller drew cheers at Thursday’s Cinema Society showing. Among those at the Gilt Man/Grey Goose party at Acme, which later moved to its new downstairs lounge, were Kyra Sedgwick, Kevin Bacon and Debbie Harry.