There is nothing confirmed but she could be playing the role of Jane.
"There were no auditions," a source on the site says. "They just offered it to her outright, and now they're in negotiations. They've been going back and forth."
In fact there is currently an online petition from Twilight fans to have Fanning play the role. The petition tells Summit Entertainment that Fanning is "perfect" for the part.
New Moon is expected to start shooting this March. The plan is for it to be in theaters by November 20.