Summit production president Erik Feig said, "Catherine did an incredible job in helping us launch the 'Twilight' franchise, and we thank her for all of her efforts and we very much hope to work with her on future Summit projects. We, as a studio, have a mandate to bring the next installment in the franchise to the big screen in a timely fashion so that fans can get more of Edward, Bella, and all the characters that Stephenie Meyer has created."
Creative Artists Agency, which represents Hardwicke, declined to comment for this story. Hardwicke's publicist declined to comment beyond the released statement. Summit did not respond to repeated requests for comment.
"This is a movie being driven by the young star that teenage girls want to see," Jeanine Basinger, the film studies chair at Wesleyan University in Connecticut, told ABCNews.com. "On that basis, the director seems expendable. The fact that she's a woman makes it sadder for those of us who worry about how few women directors there are. The irony is the fact that she is being treated as an equal -- how a man would be."
But some industry watchers question whether Hardwicke was treated fairly. After one blog quoted a Summit insider as saying Hardwicke was "difficult" and at times "irrational." Silverstein shot back, "Why don't you just call her 'bitch?'"
The news comes as Hardwicke is in the midst of a European tour promoting the film, along with stars Kristen Stewart, who plays Bella Swan, and Robert Pattinson, who plays her vampire lover.
It also comes at a bad time for women directors. According to the Center for the Study of Women in Television and Film's annual study, "The Celluloid Ceiling," women made up 6 percent of directors last year, down from 7 percent in 2006 and 11 percent in 2000.
Martha Lauzen, who directs the center and annual study at San Diego State University, told ABCNews.com that Hollywood is "in the midst of a multiyear decline," not just for women directors but for producers, writers and cinematographers.
"It's called prejudice, discrimination, gender stereotyping," director Martha Coolidge told ABCNews.com, stating the reason she believes there are so few women directors. "Why are there not more of them to pick from? They're not hired in the first place. We're told: 'Women are too soft; they can't take the heat; women don't really want to do this job.' It's frustrating to women like myself."
Coolidge, who, in four decades, has directed such features as "Valley Girl," "Rambling Rose" and "The Prince and Me," is heartened by the fact that people are talking about Hardwicke.
"At least a woman has directed a big hit and it's actually making news," she said during a break in shooting on her latest project, "Tribute," based on a Nora Ephron novel. "This is the situation men have been in, and now we've got a woman in it, and that's good."
"It's a boy's town," Silverstein said. "Directing is the ultimate job. You are the king. You tell people what to do and you're in charge. And there's a very small list of men who are on it. Here's a woman who made it on the list. She worked her butt off, achieved a big box-office success and has been summarily kicked off the list."
Coolidge said the thing to watch for now is Hardwicke's next project. Variety said she has two in the works with the company that produced her film "Thirteen."