Just a quick update after some more investigation: The mp4chaps utility from the mp4v2 project seems to be able to read QuickTime Chapters. I have tested it with the file "Engadget_Podcast_159.m4a", and it displayed the chapters correctly.

This means that it is just a matter of time to get Enhanced podcast support into Panucci. (Enhanced podcast functionality is mostly a thing that should be implemented in the player, and gPodder itself does not playback episodes - one uses the Media Player or Panucci for that). Hope this is good news for you