“Multimedia search firm Blinkx is the latest to use Really Simple Syndication (RSS) to make it easier for people to find the web video and audio they want. Users can look for any word uttered in news videos, podcasts and video blogs. […] Blinkx’s service uses smart voice recognition technology to scan video and audio it finds on the web. A searchable transcript is then automatically generated.”
BBC
some links added
Good Noodles.