Euler's Gem was the recipient of the 2010 Euler Book Prize, by the Mathematical Association of America.
From the MAA website: "The Euler Book Prize shall be given to the author or authors of an outstanding book about mathematics. Mathematical monographs at the undergraduate level, histories, biographies, works of mathematical fiction, and anthologies shall be among those types of books eligible for the Prize. They shall be judged on clarity of exposition and the degree to which they have had or show promise of having a positive impact on the public’s view of mathematics in the United States and Canada."
You can find photos of the Joint Prize Session on the AMS website and in MAA Focus, and you can read the prize citation (pdf).
Euler's Gem was selected by Choice Magazine as an Outstanding Academic Title for 2009.
Euler's Gem was the book of the month selection for the Scientific American Book Club in February 2009.