I love "superpower" comics. In one sense, they are about wish-fulfillment: Wouldn't it be neat to be able to fly, have x-ray eyes, and whatnot? In this superficial sense, reading about characters with powers can be fun.
But powers can also be treated more seriously. I haven't read an X-Men comic in years, but they were a good example of showing powers with consequences, e.g., how they might affect heroes' lives when they cannot just shut them off or appear human. Other comics have taken the concept of powers to more serious, even frightening extremes (e.g., Watchmen, Rising Stars). Still others take a fresh, humorous approach (e.g., Crossovers).
I love comics that do not use super-powers, too (namely, Strangers In Paradise). But powers are near and dear to my heart. There is so much variety in how they are portrayed that there's always something fresh.
