The story begins with Rupert, the book's amazingly endearing hero, out on a quest to kill a dragon at the end of the darkwood. His noble steed is a unicorn. Hes out to be a hero. Until this point, most readers will think, 'Wow. Stupid cliche fantasy plot #901123'.' And then the world explodes. You get to know that the unicorn is an awesome guy with a biting sense of humor and without a smidge of respect for his owner. (In fact, the Rupert-Unicorn equation is quite similar to the Loiosh-Vlad relationship in Steven Brust's Vlad Taltos
The good parts of this book don't require a lot of explanation. The plot is interesting and complex, the characters are really well-fleshed out (except for the main villians, the 'demons', and even among them the Demon Prince is someone I'd really like to read more about), the suspense is quite hard to guess, and honestly the inter-personal relations of the characters, especially with respect to the choices they all have to make under pressure in this book are beyond description. One has to read this book to accept the enormity of the decisions that these characters make. The kind of books and authors who manage to make this work are really rare, and this book definitely works.
Final thoughts: A fun, and yet at the same time really deep book on how heroes are sometimes made from the most unlikely situations. Definitely a must-read for anyone who has read a lot of fantasy (and its cliches) and almost anyone with a sense of humor.
Other thoughts: Unfortunately, I didn't have internet for nearly a week. In the meantime I've finished reading Julia Quinn's Brighter than the Sun, finished about a quarter of A Thousand Splendid Suns, and acquired some more books to read this diwali. Look forward for a lot of reviews.