I really enjoyed this book, urban fantasy with humor is exactly what I have been craving and this book delivered in spades. 
 There are a lot of reviews explaining exactly what is so great about this book, so I will just explain why I didn't give it five stars. The main reason is just that the author floundered a bit with her main character, I think that she wasn't 100% sure how much Sam should know and what Sam's true powers should be like until after this book. That really only becomes noticeable when you read further into the series, but here Sam's power/knowledge is a bit vaguely described (not knowing about werewolves, etc.) and later on she is much more powerful and better off. 
 Other than that, the book is great, it has a nice sense of humor, although it is not a laugh-out-loud book. It is pretty simple and I ran through it in just a few hours, but I couldn't wait to dive right into the next one :).