I'd give this book a 5, but I want to be selfish with my 5 stars, I want to wait for that book that completely blows me away, the book I will keep thinking of years from now, the one I will weep over when someone looses my copy! 
 That being said, this was a pretty good book! Goodman built an interesting world with engaging characters. 
 Eon won 100 points with me for NOT containing a Y.A. romance somewhere within its pages, it was pure action and intrigue. Good job Goodman. 
 I am looking forward though for at least SOME romance in the next one, now that she's Eona ;). So glad this is a duo-logy and I can run down to the bookstore and get to the ending. I'm very excited about the shift and the twist that occur in the end, I can't wait to see where she takes it from there. 
 I don't really have anything negative to say about the book, except maybe it was a little slow at the beginning, but all world building books start of slow so I can't say anything. 
 Other then that, I had a small issue with Eon's past, Goodman kept it very obscure, throwing references here and there that I just did not relate to, especially with the hip incident, it fell flat for me. 
 Conclusion. If you like Y.A., Fantasy & girl power books go buy Eon.