In the most recent episode of Smallville called "Legion", the Legion of Super-Heroes travel back from the 31st century to the present where they meet Clark Kent. Throughout the episode, they refer to Clark in the past tense, making it clear that he wasn't around in their time. Also, on the animated series Legion of Super-Heroes, it's the same thing. No Superman and a big museum dedicated to him which includes his costume. So my question is this... What became of Superman?