Rumor mill says that there might be an Obi-wan/Darth Maul film under consideration between Eps. III and IV. Not sure how I feel about it, but then I'm really not sure how I feel about any of these standalone films. It would be nice to see closure with Maul, but I'd rather see it in The Clone Wars.
As a side note, if you play Duel of the Fates backwards, you can hear that the choir is actually singing, "Maul is dead."
;)