A few years ago, the Sound recording copyright symbol or Phonogram symbol wormed its way into our hearts or at least into Unicode 2117. Did ℗ catch on? I've never seen a single ℗ in use yet I keep makin' em . . . like a ℗ machine pounding out ℗ after ℗, week after week.
I'm pretty certain it stands for 'publishing' as the C in a circle stands for Copyright. I'm not sure what you mean by the question as to whether it caught on. I've done a fair few CD designs (including my own latest album recently) and I've always included this symbol, and I'm sure nearly all my CDs have this symbol, so I'm surprised you haven't seen it.
JH
EDIT - Typodermic, I stand corrected, having seen the definition in Wikipedia. I still see it on CDs all the time though.
JH
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