Andrew Y. Grant's Nearly Human is an entertaining exploration of the many similarities between people and gorillas. It's a quick read -- I finished it in a week or so at an hour a day (and I am not the only non-skimmer in the immediate family). The text is liberally illustrated with black-and-white drawings, many of gorillas in very "human" poses captioned with text of one might be saying to the other.
Though the text is concise, the book is certainly not light on content. There is an appendix describing, for example, the differences between the different subspecies in greater detail than the earlier text. And though the gorilla is endangered, Grant keeps a generally calm -- even upbeat -- tone through most of the book, and provodes a list of conservation groups (with links) for those interested in helping out. There's also a thourough bibliography giving chapter-by-chapter references.
Caveat: I had an advanced reader's copy, which contained many, many typoes and used a very annoying Courieresque typeface. The index and a good portion of the art were also clearly missing (with "art to come" placeholders); I hope that the errors and the typeface were fixed when the index and art were put in.
* Nearly Human on LibraryThing.
* Permalink for my review there.
* Early Reviewers discussion group.