There's an old saying that goes "don't change horses in midstream." Never is this more true than when you're talking about major Hollywood franchises. Rabid fans become comfortable with a long-running series' established mythology, and it's jarring to see a new face operating under a familiar name.

I wonder then what you Twilighters make of today's news, that Bryce Dallas Howard will step in to replace Rachelle Lefevre in the villainous role of Victoria for "The Twilight Saga: Eclipse." Lefevre filled the role in both "Twilight" and the upcoming "New Moon." The Hollywood Reporter reveals that the casting switch comes as the result of a scheduling conflict, as Lefevre will join Dustin Hoffman in the soon-to-shoot indie drama "Barney's Version." Read more...

FROM SPLASH PAGE: With yesterday's announcement that War Machine will make his debut in "Iron Man 2," the question now becomes: how much of a role will the character play in the much-anticipated sequel?

We cornered actor Don Cheadle during an "Iron Man 2" press event to get his take on the character and how much of him we'll see in the Marvel Studios blockbuster.

"War Machine makes a very impactful appearance in the movie," Cheadle told MTV News. "It's significant."

Continue reading Don Cheadle's comments on War Machine in "Iron Man 2" over at SplashPage.MTV.com.

FROM SPLASH PAGE: We may never know what ultimately led to the Don Cheadle/Terrence Howard switch on "Iron Man 2," and if Robert Downey Jr. knows, well, he isn't talking (at least to us).

But one reason it definitely did NOT happen is because the character of Jim "Rhodey" Rhodes was scaled back for the sequel, "Iron Man 2” screenwriter Justin Theroux told MTV News. "I can't really speak to the plot stuff and all the rest of it but Rhodes is completely present in a very strong and big way," Theroux said of the man who would be War Machine. "He's COMPLETELY present."

Read more about the Don Cheadle/Terrence Howard shift and the future of War Marchine in the "Iron Man" sequels over at SplashPage.MTV.com.

FROM MTV.COM: While news of Jon Favreau, Robert Downey Jr. and Don Cheadle coming back on board for 2010's "Iron Man 2” has been talked about for the past few months, today, Marvel Studios made it official via press release.

However, the big news which should delight fans everywhere is the studio has also confirmed that the three will be involved in 2011's sure-to-be-mega-hit, "The Avengers," with Downey and Cheadle reprising their roles as Tony Stark/Iron Man and James "Rhodey" Rhodes/War Machine, respectively, and Jon Favreau signed up to executive produce.

Read more about these breaking "Iron Man 2” and "The Avengers" announcements over at MTV.com!

FROM SPLASH PAGE: After a morning of breaking news about Don Cheadle taking over the role of Col. James "Rhodey" Rhodes from Terrence Howard in "Iron Man 2," we recalled a recent interview with Cheadle where we asked the actor if he ever considered taking a role in a comic book film, and if so, who he'd like to play. His answer may astound you...

"Vanilla Man!" the actor laughed. However, Cheadle quickly followed up his reply with his thoughts on comic films and whether he had any interest in landing a role in one.

"I’d love to do that, I love comic books," replied Cheadle. "Unfortunately, there’s not a lot of black superheroes that they’ve made comic books about, so maybe we have to go the other way, create one in the film and then create a comic book about him."

Or, in his case, land a role as Col. Rhodes, Tony Stark's right hand man who will most likely don the sleek silver armor of War Machine in the upcoming sequel to "Iron Man."

Read more of "Iron Man 2" star Don Cheadle's thoughts about superhero films over at SplashPage.MTV.com.

"Iron Man," one of the year's biggest blockbusters in the theater (and the best-selling Blu-ray in the history of the format), will be minus one of its original marquee cast members when sequel production begins now that actor Terrence Howard has been replaced by Don Cheadle in "Iron Man 2."

The news of Howard's departure broke late last night, and came as a surprise to, well... just about everyone. For months, the actor had been telling anyone who would listen how excited he was about reprising his role and possibly donning the "War Machine" armor at some point in the franchise. Read more...