Nikki Finke at Deadline Hollywood is reporting that Mickey Rourke has finally signed on for Iron Man 2 and that the pay will be “significant”.

It’s certainly great news to see the Oscar contender in one of the most anticipated films of next year – a superhero flick no less! In addition to the announcement last week that Samuel L. Jackson is signed on for a 9-picture deal with Marvel, this news helps ease some of the worries over contract controversies Marvel has been getting itself into recently.

The report also points out that Rourke’s agent, David Unger, was able to negotiate a deal up to a “significant” salary – we can safely assume this is “significantly” higher than the $250, 000 he was reportedly offered when news first broke of Rourke negotiating for a role as the main villain in Iron Man 2.

Finke also points out that Rourke was being considered by Sony to play a villain Spider-Man 4. I wonder what villain that was supposed to be?

Interestingly, Sam L and Rourke both had ICM negotiate their deals and were both apparently low-balled with initial offers… and now both got their contract terms improved and both are set to appear in the Iron Man sequel – Good news all around.

With that cleared up (Marvel has yet to officially announce this), we still have to figure out who exactly the villain will be. There’s still widespread confusion over this as the initial Rourke casting rumor came with the following description from Variety:

“Rourke is in discussions to play a villain described as Tony Stark’s Russian alter ego, a heavily tattooed bruiser who is in the arms trade and battles Iron Man in his own nuclear-powered armored suit.”

This character description obviously hinted at the villain Crimson Dynamo as Screen Rant master Vic pointed out. However, all of the movie sites were split on this with some speculating the same as us and some reporting that he would be playing the villain, Whiplash.

Things got a little more confusing in early February when Iron Man star Robert Downey Jr. revealed that Rourke’s not playing Crimson Dynamo. When asked the question of whether or not Rourke would play Whiplash instead, Downey dodged the question and hinted at some combination of the two.

And here’s another casting update that just broke: Scarlett Johansson will be playing Black Widow not only in Iron Man 2, but in subsequent Marvel movies including The Avengers. Word is that quite the opposite of Rourke’s deal, hers was pretty cheap. Scarlett as Black Widow was first floated about a month ago, and most fans of the comic cook character are NOT happy with her as a choice to play the Russian super-spy babe.

What do you think of Rourke’s involvement and Scarlett Johansson as the Black Widow?

Iron Man 2 starts shooting this spring and is set to hit theaters on May 7th 2010.