Variety is reporting that A Song of Fire and Ice, the seven-book fantasy series by George R. R. Martin, will be adapted into a dramatic series for HBO.  Each volume in the series (four of the seven volumes have been released) will serve as the basis for one season's episodes. 

Martin will write one episode himself each season. 

There's plenty of merchandise in addition to the novels.  Game of Thrones, the first volume, has been adapted into a CCG and board game from Fantasy Flight Games, and an RPG from White Wolf.