The case has been going back and forth for a few years over the rights returning to the creators, based on the Copyright Act of 1976. The Act basically states after a certain period, creators can reclaim the rights to their creations, albeit with certain stipulations.
From what I gather, only part of the Superman mythos would be returned to the family, and the "modern" aspects of Big Blue would stay with DC.
Variety reports that a recent article in the Columbia Law Journal, by Anthony Cheng, puts forth the notion that the Superman issue could be resolved similarly to the "Spawn vs. Medieval Spawn" case of Todd McFarlane vs. Neil Gaiman. It was ruled each character was different enough to warrant a separate trademark, as the two characters were "sufficiently distinct."
Cheng writes this could be the basis for the decision to let both sides in the Superman lawsuit continue to use Superman. As stated above, the DC Comics version would uitlize the "modern" aspects, and the Siegel and Shuster heirs the more "original" -- giving us two versions of Superman.
Furthermore, Variety states that this reclaiming of the trademark would only be applicable in the U.S., and DC would still own the international rights.
Beginning to sound a bit ridiculous?
The Siegel and Shuster family would have a "Superman" they could only use in the U.S., who couldn't fly, no Lex Luthor and company - but they would have the costume (wonder if JMS will be on board? [sarcasm]).
Meanwhile, DC would have a "Superman" that could fly, with Lex and company - but would need a new origin and costume (hmmm...now the story in Action Comics #900 where Superman renounces his American citizenzhip is beginning to make sense [sarasm - sorta]).
The status of the case is currently up in the air, as the attorney for the family is appealing to try to get a ruling to determine who owns what.
The obvious question is: Why hasn't there been some sort of settlement? That's up in the air as well, as DC is suing the attorney representing Siegel and Shuster on the basis of interference.
The feud over the rights is also the basis for the upcoming Man of Steel movie from Zack Snyder, as it was ruled Warner Bros. must begin filming a new Superman movie by 2011 or the family could sue to recover damages based on filming rights.
Obviously, there is a whole lot going on here which would take a series of articles, but do we need a split Superman...again? Hopefully, this gets settled.