Hi!
I just noticed a bug in the RDF live exports of Wikidata: they still use the base URI http://wikiba.se/ontology-beta# for all Wikidata vocabulary terms. The correct base URI would be http://wikiba.se/ontology#. I guess this has been forgotten and never got noticed yet (not sure if there are consumers of the live exports).
It's not forgotten - in fact, we have an issue for that, https://phabricator.wikimedia.org/T112127 - but we never got to defining the point when we do it. One can argue RDF mapping is still not complete - we do not support units fully, and we may have to add stuff for geo-coordinates too - but one can argue it's good enough to be 1.0 and I'd agree with it. But we need to take decision on this. Please feel free to also comment on the task.