TheyWorkForYou, which I work on, has much nicer transcripts, a much better search engine, and now speech-matched video of the House of Commons from the BBC too (though we need your help! :) ). I've written three technical posts on the technology behind the video timestamping, which I guess someone might be interested in: http://www.mysociety.org/2008/06/12/theyworkforyou-video-the-flash-player/ is the first.