I know that Japanese artists have run into this problem when translating their manga into anime. Fullmetal Alchemist was based on a Manga that was (and still is, I believe) running when the anime series finally ended. In the DVD interviews, the creators talk about how it got to a point where the anime had reached the same point in the story as the manga, and so had to deviate and create their own story from there. This led to them making up their own identities for the two or three remaining sins, since their identities in the manga hadn’t been revealed yet.

In the end, I doubt it hurt the manga much because comics are much more popular in Japan than they are here, sadly. I’m very curious to see where this goes.

Though, I’m a little surprised to hear Mignola sounding so put off by Del Toro’s intentions. I was always under the impression that the two of them were damn near best friends, and that Mignola’s approval and involvement in the movies was of the utmost importance to Del Toro when making them. Now it sounds like he’s swiped the rug out from under Mignola (which would suck if that’s the case, because I really, really love Del Toro).

Either way, I’m still skeptical because I can’t see a movie studio in this day and age letting a director decide to kill their big franchise character in the third movie.