Taxonomy is an organised way of classifying content, as in a library or filing system. In posting online, tags or meta tags provide a form of taxonomy.
Since there is such a dynamic and comprehensive amount of information readily available, there has to be a rhyme and reason to it. From the logic of search engines and their algorithms to the thoughts and reasons of users, all the information is simply data without a way to access it in a way that makes sense.
Providing contributors to a site with a set of categories under which they can add content is offering a taxonomy. Allowing people to add their own keywords is to endorse folksonomy.
Folksomomy allows the dynamic process of change and development to adapt to your message and media. New slang, jargon and buzz words are often part of popular culture, or folksomomy, first before they are part of the accepted and standard culture, or taxonomy, next. The challenge is to not appear dated or cliche as a part of the process.
As a marketer, following folksomomy is is important since this allows you to understand and interface with emerging markets, groups, publics, movements and opportunities. It is the smart marketer who plans to see the natural emergence of an opportunity who can take advantage of it . Without planning and awareness it is easy to miss opportunities, even when they fall into your lap.