Stuffy members of the radio industry might be forgiven for thinking that the fuss over 'podcasting' is nothing more than a new kind of fly fishing technique. Geeks blogging on Slashdot is one thing - but when Business Week, the bible of conservative CEO aspirants calls it a "New Radio Revolution", the broadcast luddites had better take notice.

Podcasting refers to making online audio files available for easy and direct download to a user's computer or Apple iPod for listening. Streaming music and radio programs online is not new, and as Business Week reports, internet radio after an initial spike in uptake, has now levelled out in usage.

Podcasting is quite different from broadcasting in that unlike an online radio station, it does not require a user to be listening at a particular time to hear the content they want. Users subscribe or search for podcasts of interest, and these are then automatically downloaded to an MP3 player for them to listen to at their convenience.

There are a number of reasons behind the growth of podcasting. Firstly, just about anything vaguely iPod related, from custom pod cases to Apple's music download service, is booming at the moment. The other factor, is the clever way podcasts have managed to integrate with the nature of weblog publishing - itself a massive social trend. The genius of Adam Curry, who helped seed the platform was to add the concept of 'enclosures' to the RSS distribution format - allowing audio content to be attached to a RSS feed by means of a URL pointing to the file.

RSS feeds, which are what weblogs use to automatically share headlines and content between sites, are not only the key to understanding the organic growth behind the platform, but also its inherent economic advantage to content publishers. Hosting an internet radio station can be very costly, as you have to cover the data transport costs from your server. Podcasting reverses the economic equation, by requiring users to subscribe to your feed, and then download your content to their computers.

At the moment, just like the early days of desktop publishing, there is considerable excitement about the opportunities for amateurs to create and syndicate their own shows. Longer term, however, the real benefit of the feed subscription model may be to established content brands looking to distribute a range of both audio and video content without resorting to decentralised P2P systems.