Comic book writer and recently announced Chief Creative Officer of DC Entertainment, Geoff Johns confirmed in a tweet that Mark Strong (Kick-Ass) has been cast as Sinestro in Green Lantern:
Back from an amazing trip to Green Lantern town a.k.a. New Orleans!! Ryan IS Hal. And Mark Strong is going to be a brilliant Sinestro.
Starring Ryan Reynolds and Blake Lively, and directed by Martin Campbell, Green Lantern is scheduled to hit theaters on June 17, 2011.