In reading the recent http://pro.europeana.eu/files/Europeana_Professional/Publications/Metadata%2... summary I think that some of the principles apply to Commons as well, tohugh of course we're talking of very different beasts.

For instance: * "Data should be enriched where possible (e.g. through multilinguality or vocabularies)" is something we do better than most, even though further integration with the Translate extension is needed; * "using a preview portal as a means of data validation" is basically covered by the CommonsMetadata tracking categories, also visible on preview (though I don't know about GWT); * "A thumbnail should be made available for all digital cultural heritage objects" is easier for us but still a strength we tend to overlook.

Other ideas?

Nemo