MediaWiki currently does not support access to prior states of its articles using the Memento time-based content negotiation paradigm [1,2,3]. Memento allows browsers to request resources at a particular point in time, and for TimeGates to then redirect the browser to the version that was accessible at the requested time. As MediaWiki maintains all versions, it is the most authentic and knowledgeable source of this information, compared to (for example) the Internet Archive's very sparse collection of articles. MediaWiki is the best placed to efficiently and accurately provide this information, rather than a third party system.
Users wish to see versions of resources both before and after certain events, for example one might wish to see the page about Michael Jackson both before and after his death, or follow the evolution of the description of the TSA's approach to air travel security since 2001.
Editors can also benefit from Memento access to see where the hot spots of activity are, and the differences before and after editing wars.
By exposing Memento TimeGates, MediaWiki allows for time series analysis of its resources, either by extracting information from the article (text mining, data extraction, etc) or from the upcoming data platform. As the information may change many times, allowing fine grained access is extremely valuable compared to the DBPedia implementation.