Have you seen the statement from Summit? Its on Twilighters.org.

there's been a total of 3 statements. Summit released the first one, Rachelle replied, then Summit lashed out once again. To be completely honest, Summit's just doing it for the money. They want more money, and they think by hiring a more well-known actress is going to bring in more money. And I think that's ridiculous. Summit has re-arranged schedules before to fit shooting. With Cam during Twilight and with Jackson with Eclipse shooting, planning to start August 17th, but rehearsals next week. So, why shouldn't Rachelle have the same treatment. Maybe it was a failure of communication. And even if she didn't contact them like she should have, they could have sorted this out without replacing her. Honestly, they fired her because there was another opportunity. A loophole. And Bryce Dallas Howard happened to be in the loophole. They hired another actress with her well-known father and her "more credit" acting. And I hate that they judge because of the "cred". It's insulting. That's how the business works.

In New Moon, people think she didn't have a big part, but her presence is there. And there are some scenes that she's in. People are going to recognize that it's a different actress. Summit thinks they can pull a blanket over our heads, but they're wrong. The fans are much smarter than that. The fans are angry. And they should be. They're raking in the money, our money. And I think they should do what's best for the fans since we've been the ones that has given Summit it's name. It's unfair.

If they really wanted to keep Rachelle, they could have settled it a different way. Summit should stop coming out with the "scheduling conflicts" excuses. The fans see right through it. It makes them look greedy. They need to get off their high horse. It's not good for business, and they lose respect. Actually, I'm pretty sure they already have.