This from THR...
Marvel has been keeping a very tight lid on the script for the sequel, being written by Justin Theroux, but it is known that Rourke would play a tattooed Russian heavy named Ivan who becomes Whiplash, a man with deadly, technologically enhanced coils.
NOTE: Several other sources are saying that it is in fact The Crimson Dynamo that Rourke will be playing, which would make more sense--especially because insiders have said that the villain would be Iron Man's Russian counter-part.
Rockwell would play Justin Hammer, a multibillionaire businessman and a rival of industrialist Anthony Stark, AKA Iron Man, being played by a returning Robert Downey Jr.
Rourke and Rockwell would be joining a cast that also includes the returning Gwyneth Paltrow and Don Cheadle, who is replacing Terrence Howard, making for one eclectically cast summer blockbuster.
Another part -- one for Stark's assistant Natasha -- is still open.
The project is eyeing a spring start in Manhattan Beach. Paramount will release the movie May 7, 2010.
Rourke, repped by ICM, is making the best of the accolades he is receiving for his heart-wrenching turn in "The Wrestler." On top of this big-budget movie, the actor, who will next be seen in "The Informers," just joined the cast of "The Expendables," an action movie starring Sylvester Stallone, Jet Li, Jason Statham and Dolph Lundgren.
If Rockwell's deal makes, it would mark a rare studio appearance for the actor, who is best known for his indie dramas. Gersh-repped Rockwell recently starred as a sex-addicted con man in "Choke" and an estranged husband in "Snow Angels." He can currently be seen in the political drama "Frost/Nixon."