http://en.wikipedia.org/wiki/Semantic_wiki#Example answers the question but doesn't make the point, at least not to me. I don't see either any advantage or justification.

Siebrand Mazeland wrote:

Hi Steve. I assume you are talking about Semantic MediaWiki. It is hard for me to explain it by heart, so I asked my friend Google who came up with a web page. http://en.wikipedia.org/wiki/Semantic_MediaWiki appears to be a great entry point for understandable information on Semantic MediaWiki. It also contains web links for further reading.