. . "Entertainers including Snoop Dogg, Smokey Robinson and Zac Efron are also on the guest list.Fans are likely to swarm the area, too: Many waited in line for days to buy tickets for advance screenings of This Is It at the new Regal Cinemas on site, which will show the film to sold-out audiences Tuesday on all 14 of its screens.The film, culled from more than 100 hours of rehearsal footage, shows a" . . .