According to Saiyanz Rage, a source within 20th Century Fox has posted the following:
FOX is shooting for a PG-13 rating and a running time of somewhere between 3 to 4 hours. They are hoping for the DBZ movie saga to be 4 episodes long (4 movies). Starting in The Saiyan Saga, The Freiza Saga, The Android/Cell Saga, and the Majin Buu Saga.
George Lucas' CGI company ILM has signed a contract to do the special effects. Some sad news, due to casting and scheduling difficulties, filming that was set to begin real soon has been put off until Summer 2004. The original Release Date. Once the movie is finished filming and all post-production effects are added in, this movie may not be out until well into 2005.
As of right now there is no definite title. The most obvious choice would be plain "DragonBall Z", but FOX is also leaning toward "DragonBall Z: Unlimited" or "DragonBall Z: Fight For Man Kind."