Google insiders have been giving tips on how best to address some of the problems thrown up when indexing and crawling video content.
The best way of making sure a video is crawlable is to first look at the URL. Some sites unwittingly have URLs that are robots.txt disallowed. This is a sure way of limiting their crawlability. Go back to the robots.txt file and make sure it does not block URLs from your sitemap, including for the play page, content and player, and thumbnail.
Location is also key. An optional attribute restriction has been added recently to specify which territories your videos can be played. The tag will give you the option of either including a list of all countries where it can be played, or just specifying the countries or territories where it can't be played. If your videos are universal, then this facility is not relevant to you.
Thirdly, indicating the absence of any defunct or removed videos is a great help. The failure of some publishers to signal to search engines that videos have been taken down leaves the search results failing to accurately reflecting the web content. Although Google has mechanisms that detect when content and search results no longer exist, users are urged to indicate expired content for the sake of community standards.
