For people who still don't know, tagging (or as Google inconsistently calls them, labels) is the ability to categorize online stuff (like photos at Flickr, book marks at delicious or blog posts).
Tags/Labels are a very web2.0 way to discover knowledge and information as more and more stuff moves online. It is knowledge management done not by a centralised computer/person/ machine but by users themselves.
This post at the BW blogspotting blog has an interesting quote by the Cluetrain co-author, David Weinberger on how tagging could evolve:
we're also going to invent new ways to harvest tagging. Flickr, for example, is already able to cluster photographs by subject with impressive accuracy just by analyzing their tags, so that photos of Gerald Ford are separated from photos of Ford Motor cars.
We'll also undoubtedly figure out how to intersect tags with social networks, so that the tags created by people we know and respect have more “weight” when we search for tagged items. In fact, by analyzing how various social groups use tags, we can do better at understanding how seemingly different worldviews map to one another.
What is often missed in accessing 'explicit knowledge' is context of the person, time and place. If tagging is linked to social networks as David suggests then the true goal of knowledge management can really be realised. In fact David had a very simple way of explaining how tagging is related to knowledge management, which I had blogged earlier here.
On an organizational level it could smooth knowledge sharing if different divisions could help people to collaborate and form self-driven communities around practices.
Which brings us to another important point, we usually rely more on knowledge of a person we know and trust (or we know about) than someone we don't :-)