Bloody Disgusting reported the news, citing an unidentified source that claimed Ms. Page didn't like the latest draft of the script by Sam and Ivan Raimi and speculating that it was really "Oscar cold feet" that caused her to change her mind three weeks after accepting the role. (That's just silly, by the way: she lost the Oscar and now she gets pickier about her roles?) On the more official front, MovieWeb quoted an e-mail statement from Ghost House Pictures (Raimi's production house) and Mandate Pictures: "We were racing to start production so that we could accommodate Ellen's schedule. But like so many other productions trying to start before the potential SAG strike date, this one needed more time and we had to push back the start of production."
Page has proven in the past, especially with Hard Candy, that she's willing to embrace her dark side, and the idea of her starring as a strong horror heroine under Raimi's direction was compelling, so it's a shame she dropped out. Production was scheduled to start on March 17. With the start of production pushed back, that gives them more time to recast the role.