With yesterday's Wachkowski Bros / Superman rumor came the inevitable speculation as to who would be the man to fill out Superman's underoos. Would Brandon Routh return? Does a reboot mean he's out, and someone like Jon Hamm might be in? It might just be my imagination, but it seems like there's a reluctance to see Routh get the boot. Fandom has been mixed on his performance in Superman Returns but hell, fandom is mixed on Returns in general. As much as we might want a fresh start, it seems a bit unfair and strange to recast Superman already.

But what is the time frame on recasting? From the general hysteria that surrounded the Angelina Jolie-less Tomb Raider reboot, I'd say the general public feels like the actor or actress in question ought to be dead and buried. (I'm not talking about the Cinematical readers, who handled it in an objective manner. I'm thinking of regular news outlets who breathlessly announced "Jolie booted from Tomb Raider?!" As if she was weeping copiously over losing her twin semi-automatics, and not racking up Changeling nominations.)

Yet only a mild disappointment has followed rumors that Edward Norton might be replaced as The Incredible Hulk -- though we were all pretty shocked that they were remaking/recasting the character so soon after Eric Bana went green. Maybe a general numbness has set in when it comes to Bruce Banner, though, because fandom seems to simmer with a threat of violence should Christopher Nolan recast the Joker.

What would the reaction be if they recast Wolverine? Tony Stark? Would it be safe to recast the Fantastic Four?

It's a question worth putting out there. Which characters (and it doesn't have to be comic book related -- any franchise will do for the discussion. Throw in Axel Foley or Jack Sparrow if you want.) can safely be recast? Is there a time limit? Does it depend purely on the performance? Is any character truly untouchable?