The Google Webmaster Central Blog announced Google has added a Sitemaps protocol for videos. If you have videos and want to give Google more metadata on those videos to make them more searchable via Google Video Search, you now can.
Login to Google Webmaster Tools, click on Sitemaps, and select the video sitemap option. The form should look something like this:
After Google validates your video sitemap, it will:
(1) Download the video files (2) Download thumbnail images (3) Index video meta data (4) Merge changes back to Google Video (5) Revisit those videos for changes
For more details, see the Google Help Documents.