He's always been my favorite comic character. His wit was some part of it, and the fact that his powers made him potent, but not invulnerable (without stories needing stupid gimmicks like Kryptonite) also helped. The major thing, however, is that even with all his powers, he still had the same problems as everyone else. He's got everything going for him, but still gets a talking to from Aunt May because he forgot to pick up the groceries. He's super smart, but still has to work his way through school with a crappy boss. And even with his life in constant chaos, he still chooses to help other people even at the cost of making things more difficult for himself. That, to me, is a true hero and a character I can relate to.