From Starwars.com: July 24, 2004
starwars.com is pleased to announce that Star Wars: Episode III Revenge of the Sith is the full title of the next Star Wars film, scheduled for release on May 19, 2005.
The Sith are masters of the dark side of the Force and the sworn enemies of the Jedi. They were all but exterminated by the Jedi a thousand years ago, but the evil order continued in secrecy. They operated quietly, behind the scenes, acting in pairs - a Master and an Apprentice - patiently biding their time before they could take over the galaxy. In Episode III, they'll finally exact their revenge on the Jedi.
The title was publicly revealed today in a special presentation to a packed audience of Star Wars fans at Comic-Con International in San Diego, California. "For some time now, the naming of a new Star Wars movie has taken on some special meaning among core fans, who love to take part in guessing games before a title is announced, and then engage in debate once it is," said Steve Sansweet, Director of Content Management and Head of Fan Relations for Lucasfilm. "Let the debates begin."