Fahrenheit 451 fireman has already walked The Green Mile?

Frank Darabont is finishing off his third Stephen King adaptation The Mist right now in what I'm officially calling the year of the King. In this year we finally got a well received movie from one of his works (1408, though I haven't seen it myself yet) and The Mist sounds and looks out of this world cool. This was also the year we finally got a name firmly attached to his 'magnum opus', The Dark Tower under the production of J.J. Abrams. Back to Darabont and what's a little surprising is that his next movie after The Mist will not be adapted from a Stephen King book. Instead it's the much delayed adaptation of the Ray Bradbury novel Fahrenheit 9/11. I know nothing of this book but apparently the lead role is that of a fireman and the scoop AICN have is that Tom Hanks will end up with it. Hanks of course worked with Darabont on The Green Mile back in 1999. I hated Hanks' casting in The Da Vinci Code and although I know very little of this subject matter, this seems to be like a studio cash-in casting. The one where you have to find yourself a big name for your movie to be marketable to the public and not necessarily the actual right guy to lead your film. Don't shout at me though, I could be wrong... I don't know about the project. Maybe he's perfect for it?