The Digital Bits reports that we may finally see something approaching a "director's cut" of Superman II, with the footage that was shot by Richard Donner but dropped when the producers -- those weirdly fascinating, disreputable international showmen known as Alexander and Ilya Salkind -- fired him from the picture and replaced him with Richard Lester.
Since Donner was fired before he had shot all the footage, no true director's cut is possible; particularly since (like the Salkind's previous blockbusters, the Musketeers movies) Superman and Superman II were written and shot as one long movie and then broken up in confusing ways. Still, there's no doubt that putting back Donner's footage, and throwing out some of Lester's, would result in a better film; this site details what Lester re-shot at the Salkinds' urging.
Mind you, I'm not that big a fan of the Superman movies -- my favorite incarnation of the character, even above the Fleischer cartoons, is the original '30s incarnation where he was kind of a hard-boiled reporter and actually competed against Lois for newspaper stories.
But what's interesting about the fate of Superman II is that much of the critical response to the film was done along straight auteurist lines. Because Lester was a critical favorite, and Donner wasn't (and based on their overall bodies of work, this is perfectly correct; Donner is a competent technician who happened to be right for this particular project), many reviews of Superman II said that it was better than the original because Lester was so much better than Donner -- and then wound up citing Donner's scenes as examples of how Lester was deepening and improving the series. Look, for example, at Dave Kehr, at that time the critic for the Chicago Reader, who praised "the distinctive Lester touch," tried to put it into the context of Lester's whole career, and cheered for its avoidance of Donner's "facile camp." Another critic pointed to the superior skill with which Lester handled Gene Hackman, prompting the writer, Tom Mankiewicz, to write him a letter revealing that Lester never worked with Gene Hackman (Hackman quit after Donner was fired). The lesson, I suppose, is: don't be too confident that you can spot the distinctive individual touch of a director or a writer in a movie, because if you do it too often you're guaranteed to say something provably wrong.