Well, he does front his own rock band.

Having seen the Bacon Brothers in concert (shut up, they were opening for the Nields), I can say with authority that being a movie star with a rock band has very little to do with singing ability.

Yeah... I've seen some decent crossovers from the other direction (Bowie leaping immediately to mind), but Christian Kane is the only actor I've seen who might actually have had a career as a musician without benefit of the notoriety from acting. And his band hasn't hit it big even so.

Kathleen "Bird" York [link] is pretty good, although I'm uncertain as to whether her acting career preceded her musical one.

Bruce Willis and the Accelerators!

Okay, I have no idea how they are, but I like Bruce Willis and I like the name.

When casting big-name actors for Broadway musical adaptations, you can't really hope for Broadway-quality voices most of the time, sadly. However, there are better choices and worse choices: I thought Ewan MacGregor and Nicole Kidman both had perfectly decent voices in Moulin Rouge (not that the parts were extremely vocally demanding), for example, while, on the other hand, Richard Gere was so the opposite, vocally, of the crooner Billy Flynn (Chicago) is supposed to be that his solo caused the broadway musical freak in me physical pain. He did ace the acting parts of the role, though, and everybody else was decent, so that one caused me few complaints.

Based solely on the trailer, it looks like the cast of Phantom of the Opera was chosen for some completely unfathomable reason that has nothing to do with singing talent (the last note of "Music of the Night" in that trailer truly screeches painfully through my head. I do it better than he does there. And the sad thing is, they had infinite chances to make it not suck, and it still sucked!) OR huge Hollywood names. But that's another complaint for another time (and after I see the movie, maybe I'll change my mind. But I doubt it.)

The only real question I have for a Sondheim movie is this: will they actually let Sondheim be involved? After all, he's very much alive. I hold out hope that he won't allow a movie to be made without him getting input on the cast and direction.

EDIT: On the other hand, an adaptation of the play Sweeney Todd, the one without singing (many people don't know about it), would almost certainly be awesome with those two actors. Though if the rumor actually mentioned Sondheim, then that's clearly right out.

chosen for some completely unfathomable reason that has nothing to do with singing talent

They wanted a young, pretty Christine. Then they cast her and decided they had to have young, pretty actors, or else it would look cradle-robby. Thus all the young, pretty, voiceless stars. (Raoul was actually pretty good.)

Then they cast her and decided they had to have young, pretty actors, or else it would look cradle-robby.

Right, because that kind of squick would have totally contradicted the source text.

t head explodes for the umpteenth time

Well, to be fair, the source text wasn't the novel, it was the original musical. And it did a pretty good job contradicting the novel all by itself. (shrug). Still, there really are young pretty people out there with pretty good tenor voices, if not many truly operatic ones. They could have used one of those.

A pretty Phantom is silly by either source text, of course, but this movie was never going to be a horror film. Sadly. And you can't really see whether the phantom is truly ugly when you're watching the play, usually.

Now I want to go watch the silent Phantom again...

Well, to be fair, the source text wasn't the novel, it was the original musical.

In which the Phantom is still old and creepy.

The Phantom isn't supposed to be pretty. His voice is. See, it's the whole thematic thing. Raoul's pretty (we don't much care about his voice.), but Phantom's voice should make one weak at the knees.

Nova, about Richard Gere, my gold standard for being impressed with singing and dancing by actors is "could I do better?". So, I came away unimpressed by either his singing (even more so since, having now heard Jerry Orbach do it.), or his dancing (which lots of people were very impressed with)

I fear for any Sondheim on screen. I've seen a number of movies taken from plays where the script is pretty well lifted, and the patterns are too stagey (imo) for film. Sondheim is that, with music, to the nth. Not that I don't hope it does really well. I'm just...very wary.