This was originally to be a blog post, then an article, and now its back to a (rather long) blog post. I hope it stimulates some good conversation. Enjoy!
I'd like to address a common thread among comic analysis/scholarship: the belief that superheroes are modern myths. While I usually refrain from discussing "interpretive" issues like this, I can confidently say that superheroes are not modern myths in any real sense comparable to the cultural functions that myths serve.
First off, myths provide an understanding of the world for people. They can be spiritually oriented, and can give insight to daily living. This is true as much for the myths followed by people practicing the dominating religions today as it was for ancient civilizations.
Often times, people think of myths as something in contrast to the belief systems we currently have, forgetting that myths are just as much a part of modern life as they ever were. At present, we have a variety of myths that have been popular for several millennia, featuring such memorable cast members as Moses, Jesus, Mohammed, Buddha, Krishna, Laozi, and many other figures. These myths inform and instruct their followers (and non-followers sometimes) on how to live good lives through the stories they tell.
Granted, superheroes might inform people's lives with moralistic advice, such as Spider-Man's "With great power comes great responsibility." However, the ethics they impart are not unique to the superhero genre, and don't do so any more than other forms of literature.
The second reason that this belief is troublesome relates back to my ever pervasive interest in language. Beyond a system of beliefs, myths also provided much more for many ancient cultures, where the stories began as oral traditions and only later became written down. For these cultures, myths created a memorization system to record and pass on knowledge.
In today's literate societies, when we want to know information, we can reference a book or the Internet. In a literate society, recording of events can be done with writing, so it can be looked up at a later date. Oral cultures lack this sort of permanent and fixed record, and in its stead myths can fill the same roles.
For example, some plants are poisonous. In our society, we can record which ones are dangerous in writing to reference and pass that information on to other people. Instead, an oral tradition might use a story of some god or spirit becoming that plant -- with some aspect of the story giving the reason for why the plant is shaped as it is.
Let me make up a myth to illustrate this:
A particularly stand-off-ish woman breaks the heart of a spirit because of her "poisonous" and "sharp" tongue. Out of despondency, the spirit transforms her into a plant with pointy leaves. Thus the plant is called a "heartbreaker," and is avoided at all cost.
Myths like this are found across the globe. It not only gives a name and reason that the plant is poisonous, but also offers a way to remember the plant through a purpose for its identifying features.
This is a practical function of mythology. These stories can then be passed on orally in a package that people can remember. It is far easier to remember a series of stories than to remember a catalog of encyclopedia entries.
Superheroes do none of these things.
Sure, superheroes may be a genre with fictional reflections of our culture. But saying that they are "myths" implies that the term means just "stories" of a fantastical nature. People have often emphasized how modern narratives follow the same structures as myths, like Luke Skywalker in the Hero role popularized by Joseph Campbell. However, this only means that these modern stories draw on the same "raw materials" as myths (or the myths themselves). It doesn't mean that they are myths. Literature and myth differ to the extant that they affect people's lives.
Of course, most myths are just stories -- but the cultural context of their use makes the difference in what distinguishes them. In many ways, I think equating modern comic book superheroes to mythology denigrates the belief systems and cultures of people whose lives are or were infused with mythology. If, and only if, superheroes can serve an equal function in modern society can they be thought of as mythological.
Once you consider the practical roles myths can play to a cultural system, superheroes carte blanche do not fulfill any of the same sorts of functions. Nor should they need to. Superheroes can do just fine as a literary genre reflecting the culture we currently live in, without needlessly attempting to be legitimized through unsubstantiated comparison to other inappropriate contexts.