Last modified: 2014-02-20 20:05:07 UTC
Dates like "January 2000" are not recognized - moment.js only handles ISO-like dates, and falls back to the browser for everything else, and apparently at least Firefox can't deal with this format (even though both full english dates like "1 January 2000" and partial dates like "2000-01" work). In general there are countless date formats and it would be futile to try recognizing all of them, but this one seems frequent enough to make an exception.
CommonsMetadata will soon handle <time> elements which are used a lot on Commons. This might become a non-issue after that.
What's the status of <time> elements in CommonsMetadata? Is there a card or bug filed for that?
There is now: bug 61701 Should be trivial (not guaranteed to fix this bug though).