I loved it! Gritty and realistic - no glossy, slick, cartoony puff-fiction here (not violent/gore/sex explicit either though).
I thought the author portrayed perfectly the total confusion of a mer-child suddenly dumped on land, down to his aversion to sharp angles and corners (which you won't find underwater...) Told from the viewpoints of two characters, Whistle/Henry and Princess Anne, this book has all the politics and drama of good historical fiction (did you like the Other Boelyn Girl?) and the fun of a different version of European history, with the twist of the life/language/culture of the merpeople.
I sat down with this and read the whole thing until I finished at 2:30am! This one is be a must-buy for me!