Wiki namespaces are currently so underused people may not realize their importance: they provide crucial semantic information. For instance, consider the example given in Wikidata's data model article[1]

"Obama was US Senator from Illinois from January 3, 2005 to November 16, 2008"

which yielded these observations:

• mainSnak of type PropertyValueSnak with subject "Obama", property "US Senator from", and value "Illinois"
• auxiliary Snak of type PropertyIntervalSnak with property "in office" and interval "January 3, 2005 to November 16, 2008" (the subject of the auxiliary Snak is always the statement itself).

An alternative lexical model might restate this as

"The US Senator for the place Illinois is/was the person Obama from date January 3, 2005 until date November 16, 2008".

• the prime resource being described is a US Senator page not so much the Obama page
• Person:Obama is the subject complement of this US Senator via the linking verb-property 'was' or "is"
• "for" is a property of this US Senator whose value is "Place:Illinois"
• "from" is a property of this US Senator with the value "Date:January 3, 2005"
• "until" is a property of this US Senator with the value "Date:November 16, 2008"

A significant point is that that US Senator page is named Senator:Barack H Obama (or, Legislator:Barack H Obama or Public Employee:Barack H Obama, etc); it is of type US Senator, and it has these three properties, for, from, and until. In other words, if the content from this page is to be shown on the Person:Barack H Obama page, then that content should be transcluded from the Senator page; its semantic markup need not because software can interpret transcluded material as being a "subject" of, &or organic to, the Person page.

Lastly I really don't know how developers will cognitively absorb made-up words like Snak. The need for the term does mystify me somewhat. I do think everyone seems to "get" namespaces, appreciating the clarity they provide. I hope concepts like "namespace" can be equally as prominent at this stage as Snaks in the Wikidata model. Regards, --Hypergrove (talk) 03:03, 5 April 2012 (UTC)

[1] http://meta.wikimedia.org/w/index.php?title=Talk:Wikidata/Data_model