Terrence Howard will play Jim Rhodes, friend Iron Man's alter ego Tony Stark in the upcoming Iron Man Film.
He Joins Robert Downey Jr. as confirmed members of the cast. Downey Jr. Will be playing Stark though it is unknown if he will be "in the suit" or if Iron Man will be CGI.
The Character of Rhodes has the alter ego of "War Machine" which later in the comics dons a suit similar to Iron Man and is his foe. It is not believed that the alter ego will be explored in the first film of what is sure to become a franchise series.