I'm not sure that Phantom will see the same lift in ticket sales as Chicago from the film version. Chicago had an advantage of being a lesser known musical when the film was released, so there were a number of people who had never seen the show or even heard of it before seeing the film and the film piqued their interest. Phantom of the Opera has been a monumental success for so long, that pretty much everyone has heard of it and nearly all those who have wanted to see it already have. For those who couldn't afford to see it on stage, they will see the film, but still probably can't afford to see it on stage. Phantom may have a spike in ticket sales after the film is released, but I don't think it will be for very long.
"What can you expect from a bunch of seitan worshippers?" - Reginald Tresilian