With Marvel setting a July 26, 2013 release date for Thor 2 they will probably want to start filming sometime next year, so getting a script together is a priority. And now according to Deadline Don Payne, co-writer of the first film and one of the writers on Fantastic Four: Rise Of The Silver Surfer, has been hired to write the script.
Principal photography on Thor began in January 2010 and ended in May, and the film then had a whole year of post-production. If Marvel wants an equally long production schedule for the sequel filming may begin early next year. Before any cameras roll though Marvel needs to find a new director, as Kenneth Branagh won’t be returning.