From Starwars.com:
Next spring, Masterfoods USA, producer of M&M's, Skittles, and Kudos brand candies, will roll out The Star Wars M-Pire, a promotion tied to next May's release of Revenge of the Sith. Beginning April 2, 2005, there will be collectible packaging featuring Star Wars themed M&M's characters. Dark Chocolate M&M's will make their world debut, with light and dark side colors representing the two sides of the Force. Skittles and Kudos will also have games and prizes as part of the promotion. Check out Starwars.com for more information.