Warner Bros. has assigned Greg Berlanti, who's done writing and producing for Dawson's Creek, Dirty Sexy Money, and Brothers & Sisters, to write the script for a live action Green Lantern film with Marc Guggenheim and Michael Green, according to Variety. 

Guggenheim is a TV writer who's recently added some comic writing to his oeuvre, including Wolverine (see 'TV Scribe Takes Over Wolverine'), and the upcoming Amazing Spider-Man near-weekly (see 'Amazing Spider-Man Creators Named').  Michael Green is a writer and co-executive producer of Heroes, and wrote Batman Confidential and is about to start a run on Superman/Batman.