Found this on IGN...
Actress Laurie Holden revealed at C2E2 this weekend that Stephen King could write one of the 13 second-season episodes of AMC’s “The Walking Dead.”
The episode would reunite King with “Dead” showrunner Frank Darabont, who wrote and directed three acclaimed movies based on King’s work – “The Shawshank Redemption,” “The Green Mile” and “The Mist.”
Cast member Jon Bernthal revealed also that Darabont, who wrote and directed the “Dead” pilot, will not direct the second-season premiere, but will likely direct another of the season’s installments.
Season two is expected to start airing on AMC this autumn, likely around Halloween.