From Wired, “Podcast Chaos Be Gone“:
Podzinger and blinkx scour audio content for keywords by translating the audio into text and creating an index for quick searching. It’s a significant step above traditional search engines that identify only keywords in a podcast’s metadata, such as the headline and introductory notes describing the audio file’s general content.
Podzinger, in beta until mid-December, lets users jump to the spot in a podcast where their search term appears, rather than forcing them to scan an entire program for pertinent parts as blinkx does. Its minimalist design has an uncluttered search page, à la Google. And Podcasters can link to a searchable index of their content in order to sell sponsored links to text in the index provided by Podzinger.
Both Podzinger and blinkx include information about the source of the podcast and excerpts of text translated from the podcast with the relevant search terms highlighted. But Podzinger’s information is more extensive and the results include a counter indicating where in the podcast the snippet is located. And Podzinger allows users to click on the Play button to hear the excerpt and determine its relevancy before clicking on a link to download the entire podcast.
A third search engine, launched last spring by TVEyes and called Podscope, searches podcasts but scans only for the sounds of syllables rather than full words.