Really like this idea. I wonder if we could even trial to start with a specific area such as Open Government Data. This would also be good because we sort of have something like in progress (but in need of assistance) with our mapping of initiatives, challenges, catalogs etc.etc.
Think catalogues and datasets should go in ckan.net -- for catalog use tag package-type.catalog and can use country tag (country.{iso-code} or an extra attribute country to design country)