Of course, if you watch and are familiar with the lore of the Clone Wars
series you know by now that Maul did indeed survive being cut in half and spent the next, oh, eleven years or thereabouts as a scarred and disturbed cybernetic abberation plotting revenge against Obi-Wan for his defeat at the Battle of Naboo.
The Maul arc actually came to an end (for now anyways) last Saturday morning with what - for an animated Star Wars story aimed at least in part at a young audience - was a dark and very intense story that brought Maul and Sidious face to face for the very first time since the events of Episode I.
That said, it would have been infinitely better for Maul to have returned in Episode II and even III if for no other reason than to expand his character's role and develop him into more than a one-dimensional attack dog with only a few lines. I adore Christopher Lee and like the idea of Count Dooku as a disillusioned and angry Jedi Master who leaves the order and secretly joins the Sith, but Dooku/Tyranus was never the ominous threat he should have been. Christopher Lee's portrayal was a little too sympathetic to create a truly badass, evil Sith Lord.