I'm not sure if this link has ever been mentioned on the MMD.
It talks about player sales during the "Golden Age" :

  http://www.williamgaddis.org/nonfiction/stopplayer.shtml

Philip Jamison
Pennsylvania

 [ Here's a sample:
 [
 [ "A number of magazines devoted to the player -- many of them put out
 [ by the manufacturers themselves -- were stolidly enough written to
 [ convince any player owner that his was the most important instrument
 [ in the history of music and that he was its master.  The Presto Buyers'
 [ Guide kept him up on new developments and new rolls, and the Player
 [ magazine threatened to educate him to his machine."
 [
 [ That could almost be a description of MMDigest!   ;-) 
 [ -- Robbie