Consumers are aware of podcasts, but few actually listen to the online audio content, according to a new study by Forrester Research. 

The analyst firm found that a quarter of all online consumers have expressed interest in podcasts, but only one per cent of North American households regularly downloads and listens to such content.

Forrester projected that about 700,000 US households will listen to podcasts this year, growing to about 12.3 million by 2010.

Podcasts are often considered as audio versions of blogs, allowing consumers to record shows from their homes and put them on the internet.

But the study found that most consumers prefer to listen to existing content such as radio shows rather than content created exclusively for the internet.

A podcast of existing content has the advantage of enabling 'time shifting', which allows consumers to listen to a show when and where they want. Users are also often not aware of the original content that is available as a podcast only.

Charlene Li, a principal analyst at Forrester, warned that companies should continue existing podcast programmes, but should not heavily invest in the technology.

"Companies should not be dashing out to create expensive original content for a small audience unless they gain value from being seen as innovative," she wrote on a company blog.

"Podcasting will get easier and the content will get better, but it will all take time."