As I've been doing research for my paper, I've come across a few problems. I just want to rant on this for a minute.
There are some very good books on comics. I've referenced Danny Fingeroth a few times, and I just read a very good one called Superheroes: A Modern Mythology. That said, there are a lot of those X and Philosophy books out there that really irk me. The problem is that these books are more topical, and therefore instantly dated the second the are published. For example, a book that talks about Jason Todd's death is no longer applicable, since he didn't die thanks to Superboy-Prime retcon-punching him into existence. Superheroes and Philosophy is from 2005, meaning they don't get Final Crisis or Civil War. They haven't seen The Dark Knight, read Kick-Ass, or Infinite Crisis. Superheroes and Philosophy has a whole chapter on metaphysics and multiverses based on Crisis on Infinite Earths, but all of that is reinvented by the next crisis.
Another thing is how people think Batman is crazy, and that the costume is some sort of bizarre compulsion. False. Batman is not compelled to do this, he wants to. He can stop at any time. He says so in Identity Crisis. That is an important Batman story. If you don't read it, you lack an important perspective.
I just wanted to say that. Comics are a changing universe. Things are never ever concrete.