I think they mean the actual data.
The postmeta data is stored in a table within the database.
General data (like the_time()) is returned within the post, custom meta data can be posted as well by default or with specific calls.
see:
http://codex.wordpress.org/Post_Meta_Data_Section
http://codex.wordpress.org/Function_Reference/get_post_meta
I wonder if a project would be something MU would handle better. Perhaps with a hack of the groups BuddyPost widget..
Just an Idea I’ve been having.. May work on soon..
-Dennis
