I just spotted this announcement from TVEyes, a company we've mentioned on the blog in the past. TVEyes offers technology that automatically indexes and allows users to keyword search EVERY word spoken in a television or radio broadcast and then watch the full motion video or hear the audio online.
Now, according to a news release, TVEyes technology will begin keyword indexing audio and video podcasts via a site called Podscope. The release doesn't mention precisely when the service will be available and the Podscope.com site currently says the service is "coming soon." Podcasters are also able to submit url(s) for crawling.
In January we blogged that TVEyes technology will soon allow Yahoo Video Search users to keyword search Bloomberg Business News video content.
This SEW Blog post lists other players in the video search space, several with tools that you can demo online.