This got little attention due to the Google/You Tube deal but Microsoft signed a deal with video search startup Blinkx to license their technology for some of it's MSN and Live properties.
Video search is a different beast. This is not about applying the same text search algorithms to the textual semantics on video content ( whether metadata, tagging, user comments ) but image and video retrieval that enables multimedia content indexing on a semantic level. It’s really, really hard stuff to do but researchers have been working on it for years. I expect the next 5 to 10 years this will be the area where the money ( from Google/Microsoft/Yahoo/AOL ) will be.
Link: Web Video Search Site Blinkx Signs Microsoft Pact - News by InformationWeek.
Link: ACM Multimedia 2006.
Link: ACM International Conference on Image and Video Retrieval, July 9-11 2007.
Link: TREC Video Retrieval Evaluation