Fist off, let me say that the Epic Level Handbook is well written and thought out, and gives great amounts of information on how to play your Dungeons & Dragons game up long past 20th level characters. The rules are clear and easy to follow. Overall, I suppose it's a really good book.
Perhaps it is my personal bias, but I am of the thought that characters that adventure past 20th level have something wrong with the world they live in. How is it possible, for example, for someone so powerful so as to fight great dragons before afternoon tea, to live in the same world as those people who struggle to keep the wild dogs from stealing their chickens? How would a character in this world rise above his or her station in life and find a career in adventuring, when there are beasts and other oppositions out there that are able to challenge the likes of Hercules and other larger-than-life figures? It doesn't make much sense, and tears away from the entire effect role-playing has to me: a believable fantasy world.
I am the sort of guy who believes that, no matter what level of skill and power a person attains, he can still be killed by a speeding bus.