WSJ.com - Surfing the Internet for Spoken Words: "One of the charms of Internet video and audio is that Web sites featuring such offerings are largely free of the advertising cluttering television and radio.
That may be about to change.
Several small companies are starting to pitch advertising links using their software that will search every word spoken in Web-borne video soundtracks or Internet audio programs known as podcasts. The new technology, from companies including Podzinger Inc., TVEyes Inc. and Blinkx Inc., uses voice-recognition software to translate spoken words into text or audio-wave forms that can then be searched.
Identifying spoken content of audio and video clips results in more-relevant results when using a search engine to look for a particular item or topic. From there it is only a short step to also use the new technology to match related advertising with the search results -- much as Google Inc. and others do for searches of text-based material."