Keith Urban is an artist sui generis in country music: a native of Australia who headed to Nashville to break into the business and managed to work his way to the top of the country charts, he maintained a long, successful career where he has seemed to exist just outside of mainstream country but nevertheless adapted to its shifting fashions. There are some common denominators in his deep catalog: he's a killer guitar player who never misses a chance to shred, but it's always in the service of his songs, which display his ear for melodic hooks and an openhearted sensitivity. A...