This pretty much sums it up.
http://movies.ign.com/articles/101/1014092p1.html
WB is fcked....Since Siegel and (co-creator) Joel Schuster has the right for the origins they could just sit back and not give WB permission. And in 2013 they will get everything back. Or WB has to make a new Supes movie with a new origin.
This means the Siegels now control depictions of Supes' parents, the destruction of Krypton, the infant Kal-El crash landing on earth, and so on. If Warner Bros. want to reboot the franchise and include these elements - perhaps for a new origin movie - they would now have to seek permission first.
AS previously reported, if the studio and DC Comics want to make a Superman movie they need to start production by 2011.
In 2013 all the remaining rights to the character will pass over to the families of Siegel and (co-creator) Joel Schuster in 2013, giving them the power to set up Superman projects elsewhere.