I’m using Excerpts with post-thumbnails on my startsite. Adding Images is working pretty fine. But how can I embed a video from vimeo or youtube as a post-thumbnail? Just the video in a smaller size, not a screenshot. Any ideas?
You could make a plugin which adds a meta box in admin, where you can add a link to a youtube/vimeo video. The plugin should then save the url as meta data for that article when the article is saved.
When listing the articles (or viewing a single one), check if the meta data value is set. If it is, then output the corresponding embed code instead of the post-thumbnail.