A new week - a new format: this weeks post is about metadata in Ogg Vorbis audio.
The metadata container for these files is called
Vorbis comment, which is also used in the FLAC, Theora and Speex file formats.
For a general introduction into audio metadata see e.g. the previous post in this comparison series: Part 2: MP3 Metadata (ID3 Tags).
The tool to analyze and create metadata for Ogg Vorbis files is called vorbiscomment.