what about the hulk that roles been play with so many actors I could see them replacing robert if they would making a iron man movie with a younger actor like they did with the new spider man movie so many actor that got there big pay check doing this big movies look at the early 2000 like the lord of the rings movies and ever with mel gibson with mad max they remaking those mad max movies
Ok, that's kind of not the point.
The thing is -- when you have a character that no one outside the comic book world knew (and Iron Man was nowhere near as popular as Superman or Batman), a character that even comic book readers generally thought of as too douchey and unlikeable, and he becomes incredibly popular and mainstream by virtue of having the perfect fit between character and actor in the film, it definitely matters.
And it is because of the actor. Robert's casting is a bit of a lightning in a bottle scenario. For example, 'Iron Man 2' was hated by the critics (that 74% on Rotten Tomatoes is deceiving) but time and time again in the reviews, the saving grace of the film was Robert as Tony.
Johnny Depp is to Jack Sparrow as Robert Downey Jr. is to Tony Stark.
Sure, in the future they'll probably recast. Nothing is sacred in Hollywood. But I think Kevin Feige is in the wrong for discussing this now, especially considering that Iron Man 3 hasn't even started shooting, The Avengers is not even out in the US, and Robert is all but signed up for Avengers 2. The earliest this should be discussed is around 2015.
Until then, I find this whole thing pretty insulting to Robert. It's like he was already being dismissed even though he has TWO more Marvel films coming up in the next 3 years.