I don’t know too much about the Green Lantern as a character, but I know that the casting rumours at present are giving me no confidence or interest in jumping onto another comic book franchise.
The most recent name thrown out has been Chris Pine, the man about the burst onto the map by playing a young Kirk in JJ Abrams’ Star Trek. This has been disputed but his name being bandied around does indicate a desire from the studio to cast someone young and spunky in the role. Elizabeth Rappe on Splash Page notes the screenplay calls for someone at 27 years old, something neither Chris Pine or Anton Yelchin can pull off. Rappe has also listed a few possible other candidates for the role, including David Boreanez.
Her others are much stronger however. Jon Hamm would be significantly older but I would argue this is an actor that changing that age, which doesn’t seem to be integral the the story, would be a worthwhile move for. Nathan Fillion would be even better, bringing a titanic-level of charm to the role, slightly similar to Downey Jr in Iron Man, and a man who has already played superhero and regular heroes in the past. Then she notes Jamie Bamber and Tahmoh Penikett, both veteran of Battlestar Galactica and both deserving of a chance to jump into the quality action movie world.
I am definitely going to need to see a decent lead actor in the role to even remotely peak some interest in the project. I will have nothing more on this with Pine or Yelchin as I honestly can’t see either of them saving anyone or being super-powered.