Really great incorporation of graphics and history of some of the original Avengers. David does an impressive job of summing up a rather confusing amount of changes made to each character throughout time. The text is humorous and at times a bit snarky (if he didn't have such an impressive number of comics with his name on them, you'd think he hated comics or something) regarding all of the transformations and weird happenings of the Marvel universe. Each character chapter also includes enclosed replicas of artwork, which is very neat.
While I personally would have liked to get more information on some of the female Avengers, such as Wasp, one of the founding members, this is less a criticism of the actual book and more a criticism of female representation in comics. Female origins come up in some chapters such as Black Widow (that's pretty much it), but understandably it is difficult to dedicate a whole chapter to a character who never had a self titled comic series.
Overall an interesting read with plenty of great art and quite a bit of information.