It looks like it came out only in the UK in September on paper, but the ebook launch wasn't region-restricted, so it's already available on U.S. Kindles. But if

It looks like it came out only in the UK in September on paper, but the ebook launch wasn't region-restricted, so it's already available on U.S. Kindles. But if you look at the U.S. dead-tree editions, January 2014 is the U.S. hardcover and July 2014 the U.S. paperback.