I did not like this book.  Overall the story is a good story with a moral of not allowing vengeance to influence your decisions.  There are only one or two likable characters.  To be honest the only character with a reasonable amount of development is the cannibal Queequeg and he is not even a main character.  You do begin to see bits and pieces of what drives Captain Ahab near the end, but not nearly enough to understand why he is so determined to kill Moby Dick.  The so called main character/narrator, Ishmael, has very little personality at all.  I guess I just had a hard time relating to the motivations of any of the characters. 
Content and story-wise, the book starts out okay and you get prepped for an exciting journey on a whaling ship...but that is pretty much where an excitement stops until the last 100 pages of the book.  Everything in between was dull shop talk and unnecessary history.  (I mean, there were three chapters about art involving whales. Why?)  It was interesting, but did not contribute to the story that much.  I truly feel you could take the 1st 100-200 pages and the last 100 pages and skip everything else in between and get the same thing out the story.   That being said, if you are into the history and symbolism of whales, and the process of Whaling, this book has a lot of it and you might enjoy this more than I did.