Why is the metadata panel on tickets empty?

[Isaac Norman]

Just installed and briefly tried out the metadata plugin.  I've associated a few keys and values in a project.  I can see that value of that in child issues if I create a custom field and map it, however I don't want to have to create custom fields for each key. 

There's a 'metadata' panel on the right of the child issue view, but it's empty.  Is this supposed to show me all the metadata fields?