And while the screenwriters of "Cowboys & Aliens" Roberto Orci and Alex Kurtzman ("Fringe") have acknowledged some script adjustments to accommodate the change, they insist that Craig's casting solidified the role.

When asked how the casting switch affected the script during a recent interview with Collider, Kurtzman replied. "It's not that it changed dramatically, it's just that it became more specific. We had been talking broadly with Downey before hand and then I think as the story evolved, it also felt like the character had changed somewhat. Daniel feels like the perfect version for us."

"The story and the structure are the same," added Orci. "The voice changes once you get an actor, you tailor it to their strength and what makes sense for them."

"I think the thing that is so wonderful about Daniel is that he says an enormous amount just with his expressions [and] with his face," continued Kurtzman. "That's his incredible strength as an actor. I think the Western is typically a genre that is very sparse in dialog in general. So he really feels like the perfect mix."

The screenwriting duo also spoke about Harrison Ford's role within the film.

"What a lot of fans will love about it is that it's a throwback to a lot of what we love about ["Raiders of the Lost Ark"], explained Kurtzman. "He's definitely like a crazy presence [in the film]," added Orci. "[We're] using the stuff we love him for but also seeing him in a new way."

Kurtzman also shared his thoughts on working with the film's cast.

"The last couple months have really been about getting in a room with the cast and talking to them and riffing out different versions of scenes. And it's been an incredible dream come true to be in there with Harrison, Daniel, Olivia [Wilde] and Sam [Rockwell]. It's amazing."

"Cowboys & Aliens" will ride into theaters on July 29, 2011.

What are your thoughts on the Daniel Craig for Robert Downey Jr. switch? Are you looking forward to seeing Harrison Ford in the film? Saddle up and let us know what you're thinking in the comment section and on Twitter!