Out of a beige windowless office in Chicago comes a product that just might revolutionize what you thought was possible on the web. X-Stream.ly is a pure play API service offering low-latency high throughput real time messaging with no server side coding required. The x-stream.ly API is a pretty competitive offering in the real time API space.
You can now use the YouTube API to access and create captions for your videos. That means you could let your site visitors refine the transcript to videos you own, or create their own versions of the caption.