There have already been many films, cartoons, and television versions of the Oz tale. Before the 1938 masterpiece starring Judy Garland, there were a number of adaptations -- silent movies and animated shorts. There have been numerous other versions since then, including The Wiz, Tin Man, Return to Oz, and the under-rated cartoon sequel Journey Back to Oz with the voice talents of Liza Minelli, Milton Berle, Mickey Rooney, Paul Lynde, Danny Thomas, and Margaret Hamilton. There have been some interesting comic book adaptations like Dark Oz and Oz Squad. L. Frank Baum's original 13 sequels to The Wonderful Wizard of Oz are all now in the public domain, so expect even more versions to hit us from all media in the years to come.
Surrender Dorothy tells the story of a descendant of the Oz heroine who returns to that magical realm to stop a war that threatens both Oz and Earth. Drew Barrymore has proven to be a savvy actress, producer, and director, so if anyone can do the tale justice it's her.
Is there such a thing as too much Oz? I don't think so. Sure, if the new tales turn out to be crap, fans of the 1938 musical will feel cheated. But I think good adaptations can stand on their own. When most people think of Oz they only recall the story elements from that MGM musical, now owned by Warner Bros. That was based only on the first part of Baum's saga. Maybe new versions will finally be able to bring the rest of the Oz tale to life in a way that will entertain and delight the masses just as that beloved movie did decades ago and continues to do all these generations later.