The ontology uri we use with the rdf mapping of wikibase used to be <http://www.wikidata.org/ontology#>. Recently, it was changed to include a version number, so it's now <http://www.wikidata.org/ontology-0.0.1#>.
This wrongly implies that this is an ontology for the content of wikidata.org, while in reality it's a low level ontology for the scaffolding we use for our rdf mapping. We, or someone, may actually provide an ontology for wikidata at some point. And we should make clear that the ontology applies to all wikibase sites.
Some options I can think of:
* http://wikiba.se/ontology-0.0.1# - but are we sure we still control that domain in 30 years?
* https://www.mediawiki.org/ns/wikibase-0.0.1/ - but the data model and rdf mapping have nothing to do with mediawiki.
Other options? Thoughts?
I believe we should fix this, and we should fix it now, before we start providing official rdf dumps. The old URI could resolve to a redirect to the new one - though it currently doesn't resolve to anything.