For collectors who enjoy collecting books about comicbooks and superheroes, this is an essential piece of your library. I am happy to own it, bu I would have been extremely frustrated if I paid the original list price.
The DC Comics Encyclopedia, by DK Publishing, reflects some of the sloppiest editorial work I have ever read from a professional book publisher. I have been in education most of my adult working life and I expect a higher standard of quality work from my teenage students when it comes to reviewing and editing their own work.
I am not qualified to evaluate the accuracy of the information but you don't need to be an expert to spot the many flaws. Many pictures are mislabeled. Some sentences just stop midway and pick up with the next sentence. I have even found what looks like editorial notes that were clearly intended for one of the many contributors. It is incredible to believe that this would miss the watchful eye of the editor and publisher and actually make it to print.
As a reference book, The DC Comics Encyclopedia still has value. I can only hope that the person or people responsible for the sloppy work are not hired on for additional projects in the near future. Comics may not be considered "high literature" but for those of us who admire the work of the creators, artist, writers, and publishers of comic books...we, along with the creators, themselves, deserve more respect than what is evidenced by the work in this book.