It was reported last week that Terrence Howard would be replaced by Don Cheadle in the highly anticipated sequel to the summer blockbuster Iron Man. Reportedly, it was due to Howard's demand for higher pay for the role. Knowing how War Machine was teased in the film made it seem like there was going to be some more development in the Jim Rhodes character. It is unfortunate for a franchise that is destined to make a lot of money to not want to put out for a little bit of continuity in a film.
This goes for all sequels that get recast, and not just Iron Man. Several that come to mind immediately are Marvel, so that's convenient. As you may have heard, Thomas Jane is not returning for The Punisher: War Zone and Ed Norton doesn't want to reprise his role as the Incredible Hulk for a possible sequel or The Avengers. Jane didn't like waiting for the project to start shooting and Ed Norton hasn't given a reason, but it is most likely due to the changes he made to the script of The Incredible Hulk being edited out of the theatrical cut.
People making choices to compromise the quality/success of a film takes it away from the consumer and makes the imaginary world that a film creates a lot more realistic. When Iron Man II comes out and you see Tony Stark talking to Jim Rhodes, won't it be weird seeing him talk to a physically different person than the one he was talking to a day/week/month/year ago? Recasting makes the audience aware of the fourth wall and consequently, makes it easier for an audience to be taken out of a movie.
Also, don't get me wrong, the actors used to replace the leaving ones usually do a good enough job, but it's not the character from the previous films. A few months ago, Mummy: Tomb of the Dragon Emperor was released without Rachel Weiss. They did something kind of smart in the film to address it. At the beginning of the film, one of Maria Bello's first lines, referencing a character based on her the she wrote in books titled "The Mummy" and "The Mummy Returns", was, "Honestly I can say that she's a completely different person." Now that seemed to be the studio telling the audience about the change, but that didn't change that the new Mummy film was bad.
To any Hollywood types reading this blog, please listen to my plea. If you go the extra mile in keeping the original talent used, not only will the profits grow, but it will be more likely to maintain a franchise.