According to sources, actress Scarlett Johansson was originally up for the role, but was unable to commit due to scheduling conflicts with Cameron Crowe's 'We Bought a Zoo.' Crowe's latest begins filming in the spring, while 'Gatsby' is scheduled to begin next summer.
Today's news marks significant progress in the casting of Daisy. Earlier this month, Deadline reported that a number of actresses were up for the role -- everyone from Natalie Portman, to Rebecca Hall to Blake Lively. At the time, Mulligan's name was not mentioned.
An Oscar-nominated actress, Mulligan has appeared twice on the big screen this year, in 'Wall Street: Money Never Sleeps' and 'Never Let Me Go.' She can next be seen in 'Drive,' opposite another Oscar nominee: Ryan Gosling.
Tell us: Is Carey Mulligan the right choice to play Daisy?