It seems that Iron Man 2 has just got its villains. The question remains however, WHICH ONES? Yesterday, E! reported that Mickey Rourke and Sam Rockwell would be on board for the metallic Avenger's sequel; Rourke as the Russian arms dealer in nuclear-powered armor called Crimson Dynamo, and Rockwell as the multi-billionare industrialist rival of Tony Stark, Justin Hammer. However (here's where the confusion sets in) The Hollywood Reporter later released info that Rourke would be playing the villain Whiplash, who in the comics is an assassin that carries a pair of deadly cybernetic titanium whips and is regularly employed by Hammer.
Hopefully we will have this cleared up soon, but Rourke as Crimson Dynamo seems to be a more ideal role for him, since Whiplash (later renamed Backlash) is a flamboyantly dressed, younger man in the comics. However, we might also take into consideration the fact that the last Iron Man film already had an armored villain, and to have another in the sequel might be going back to the well.
Despite the confusion, it will be interesting to see how this set of villains will fare. From not even being able to pay his rent, to critical success in The Wrestler and quickly becoming possibly one of the most ubiquitous film stars of the year 2009, Mickey Rourke is back for sure. Sam Rockwell (probably best known to mainstream fans as Zaphod Beeblebrox from The Hitchhiker's Guide to the Galaxy) is someone who has made his reputation for the most part on the independent scene. The character of Justin Hammer is one that is much older than him, so either they are reinventing Hammer as a younger man to paralell Stark more closely (like Topher Grace cast as an "Evil Peter Parker" version of Eddie Brock/Venom in SM3), or Rockwell was brought on board for his skills as a character actor to play an evil old man.
Personally, it is kind of perplexing why Iron Man's primary villain, The Mandarin was not utilized. Even with a subtle reference to him in the first film (the mentioning of the terrorist organization "The 10 Rings"), it seems like something was terribly missed here. Even if they wanted to do the parallel play between Stark and Hammer, that dynamic could have fit in a film centered on a conflict with Mandarin. However, WHO KNOWS? He might still be in the film, among the others. John Favreau might just be leading us in different directions with the release of this info.