The Martin Scorsese-generated blues series, a weeklong extravaganza of blues films presented on PBS stations across the country, was one of the most anticipated events of the past few decades. Given the decline of sales across the board for all genres of music, the folks who make, record and release blues music were hoping for a shot in the arm, akin to the Ken Burns series on jazz and, to a lesser degree, the country/bluegrass film "O Brother". While every label with a stake in the music releas …