Boys of Steel: The Creators of Superman was named to the Kirkus Reviews list of the Best Children's Books of 2008. It's on page 12 of this PDF. [5/18/11 update: This link is now inactive. I am waiting to hear if the list has been posted elsewhere since a quick search didn't reveal it.]
The write-up describes the book as celebrating "the birth of an American icon that reinvented the comic book and, perhaps, the nation itself."