Deadline reports that Robert Stromberg will replace Burton as the movie's director. Stromberg is mostly known as production designer and apart of visual effects department on some rather large films.
His credits include production designs for Avatar, Alice In Wonderland and Sam Raimi's Oz, The Great And Powerful. Robert also did visual effects on Boardwalk Empire, The Pacific. Tropic Thunder, Pirates: At World's End, Solaris (2002), Bad Boys 2, League of Extraordinary Gentlemen, Chronicles of Riddick, Pan's Labyrinth and Shutter Island. I have a strong feeling that this film will end up looking gorgeous but ends up more similar to the tone of Snow White And The Huntsmen.
It's interesting to see how Disney handles their live-action tentpoles considering they have to make these films different enough from their Marvel superhero films. Lone Ranger and Oz seem to keep Disney's fantasy tradition intact while staying in their respected genres. I assume like Alice, Maleficent could look unrecognizable from the original animated film.