You know who was most shocked about Don Cheadle being cast as Jim Rhodes? The previous one, Terrence Howard. "It was the surprise of a lifetime. There was no explanation. just ... up and vanished. I read something in the trades implicating that it was about money or something, but apparently the contracts that we write and sign aren't worth the paper that they're printed on, sometimes. Promises aren't kept, and good faith negotiations aren't always held up." You can hear the whole interview on NPR.
One actor who will be back is Sam Jackson, or so he told IESB. Apparently, at the Scream Awards director Jon Favreau told Jackson that Nick Fury would have a much more prominent role in the second one.