Actor Terrence Howard will not be reprising his role as Jim Rhodes (rumored to take on his War Machine persona in the next film) for "Iron Man 2," according to the Hollywood Reporter.  According to sources close to Marvel, Howard chose not to return after contract talks broke down. 
Howard's departure opens the door for a new actor, and that actor is Don Cheadle (now in theatres starring in "Traitor").  Cheadle's other roles include the "Ocean's Eleven" series, "Mission to Mars," Picket Fences, and "Hotel Rwanda," for which he received an Oscar nomination.

"Iron Man" was a surprise hit this spring, wowing audiences and setting a new bar for superhero flicks (a standard which was handily met by "The Dark Knight").  The sequel is currently being penned by Justin Theroux.  Director Jon Favreau is rumored to be hard at work already on the new film.