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Google has extended their Sitemaps to include support for videos, which means your videos will be more easily indexed by Google's Video search. In practice, this means that webmasters will now be able to create a new Sitemap in which they can specify all videos (and metadata that goes with them) on the site. One of the benefits of this, for example, is that Google will be able to generate a thumbnail of your video and place it in the search results.
See an example on the official Google Webmaster Central blog.