No screenwriters are on board. "Returns" writers Michael Dougherty and Dan Harris opted out of penning "Superman: Man of Steel," and the strike arrived just as other scribes were to pitch ideas. Internally, Warners has moved the release date from 2009 to 2010. - Variety, 1/11/07 [link]
I just got off the phone with a very high-ranking mole who is absolutely in a position to know what's happening with this film, and he tells me that it is "absolutely false" that Brandon Routh is out as Superman for the stand-alone series. The only thing that has been determined is that JUSTICE LEAGUE will not feature the actors from the other films. That's it. Right now, Routh is still Warner's choice to return if they make another stand-alone SUPERMAN film, and that's based on conversations as recently as a few weeks ago. - Ain't It Cool News, 1/4/08 [link] 
Kelvin knew about Brandon not being the new Superman for weeks and weeks now, but made a promise to the DC people that he wouldn’t break the story. Variety has now confirmed what we’ve secretly known for a while and Brandon Routh will be replaced in the stand alone sequel by whomever is cast as Superman in the upcoming Justice League of America movie. - The Beat, 1/4/08 [link]
Warner Bros. was smart enough to get Langella on contract. "Yeah, I've got two more to do," he told us, though he doesn't know when the next movie might be, "Oh, I don't know. I think both with the strike and with the fact that they haven't come up with a really great story yet, I don't know when the next Superman is going to be. My guess is that it probably won't be until next year." - SuperHeroHype, 11/8/07 [link] 
Superman Returns screenwriters Michael Dougherty and Dan Harris won’t pen the movie’s sequel - Blog@Newsarama, 10/22/07 [link]
Sadly, much of my work on Superman Returns never ended up in the final film, because at the last minute a big introductory sequence where Superman returns to the shattered remains of Krypton was dropped to help keep down the running time. But at any rate, I worked on a variety of elements for this lost sequence, including the destroyed planet itself and both the exterior and interior of a large crystalline ship which has carried Supes from earth. The interior was fully built and photographed as a translucent, glowing set which I’ve only seen in one photograph in the Art of Superman Returns book. Bryan Singer’s group has made noises about including the lost sequence in a sequel film, and I sure hope they do that so I can see how it turned out! Also cut from the release was a scene where teenage Clark Kent discovers the hidden remnants of the Kryptonian space pod which brought him to earth as an infant. - Blog@Newsarama, 9/28/07 [link]
Here's a general outline of the 3 big key points for this Superman Sequel pitch from Singer. 1.) Kryptonian character coming to Earth as a result of Supes' pilgrimage to his now dead homeworld. 2.) A new villain making a deal with Lex Luthor and then taking over Luthor's operations & Lex-Corp and using Jason as a hostage. Something happens inside this sub-plot idea which would make some SR critics very pleased. 3.) The villain is reported to be "Braniac". - Rumored pitch for film, Mania, 8/27/07 [link]
Producer Jon Peters talking with the Hollywood Reporter... "Director Bryan Singer is working on the story (for the sequel to Superman Returns), and hopefully, that will be a script by the end of the year. And hopefully, we'll be in preproduction by, say, January or February of next year." - Hollywood Reporter (and Mania Movies) [link], 5/03/2007