Well, talk about opposite ends of the spectrum... the word is that Bryan Singer wanted to make a statement with the upcoming Superman 5, casting someone in the role who is either a openly or closeted gay man, in the hopes of creating a role model for those folks.
On the other side we have Warner Brothers which wants James Caviezel, who played Jesus in Mel Gibson's The Passion of the Christ, no doubt wanting to cash in on the success of that film.
Caviezel (who seems to be a lock for the role) would be an interesting choice since the Superman story has had some parallels with Christ: Being sent here from somewhere "not-Earth", more perfect and powerful than we are, and in the "Death of Superman" storyline, Superman was even resurrected from the dead.
At the risk of stepping on toes, I'm siding with WB on this one.
Source: Comic Book Resources