Andrea’s points on Tag:
This whole new approach to aggregating distributed content across the internet, enabled by a new generation of tools that were built with folksonomy in mind, has significantly lowered the barrier of entry for broad-base participation in a common internet publishing cause.
Any internet users with very little knowledge of html can participate by including special html tags in their blog post or by adding tags to their photos inside Flickr.com. Advanced technical expertise such as software installation on a server and computer programming are not required. There is no need for a website administrator to setup user accounts for new users. Nor is there any need to worry about the logistics of setting up a domain name and securing sufficient web storage space.
This approach to content production is especially useful in case of a topic that needs to be dealt with in a very timely matter with input from a large variety of sources across the internet. Natural disasters, such as the recent tsunami and earthquake in South East Asia are good examples. (See: http://www.technorati.com/tag/tsunami and http://www.technorati.com/tag/earthquake )