Sixty years ago today – May 16, 1966 – The Beach Boys released Pet Sounds on Capitol Records.  Though the album wasn’t commercially successful upon its original release, it came to be regarded as a high watermark not just for The Beach Boys, but for American popular music itself.  The Beach Boys have just celebrated 60 years of Pet Sounds (as well as its timeless songs including “Wouldn’t It Be Nice,” “God Only Knows,” and “Sloop John B”) with a Capitol Tower reunion of Mike Love, Al Jardine, and Bruce Johnston; a…