Yahoo just announced the first beta version of its new Yahoo WebPlayer, an HTML/JavaScript video and audio player, which supports YouTube, Yahoo Video, MP3, and WMA formats. Publishers, bloggers and developers can add it to their site with a single line of code, and when the page loads, the player scans the page contents and adds play buttons next to playable items.

The company is touting it is an easy way to add video and audio to web pages, taking the complexity out of embedding various media players, supporting different formats, etc.

Searchmetrics just released a report highlighting the importance of using video in search engine visibility, particularly with Google’s universal search results. Anything that can help you get video on your site may potentially help you in this area.

“Playable items could be references to supported media or specific recognized terms, such as movie titles,” says Yahoo’s Alex Sirota, Director of Media Web Apps. “Once clicked, a play button will open a slick in-page player that will stream all the detected playable items as a unified playlist.”

Sirota gives a few examples:

1. To play a YouTube video, just link to the corresponding YouTube page, such as Mike Relm vs. Zoetrope (links to http://youtu.be/i56XeM0-b8Y).
2. To play an MP3 file, for example this Awesome Yodel, just link to it (http://mediaplayer.yahoo.com/example3.mp3) on the page.
3. To automatically find and play the most appropriate trailers and clips for a specific movie, just link to the movie’s Yahoo! Movie page, for example TRON: Legacy (links to http://movies.yahoo.com/movie/1810096458/info). You don’t need to manually go and search for individual video clips – Yahoo! WebPlayer does that automatically for you.
4. To automatically find relevant terms such as “Cowboys & Aliens” on a page and make them playable, just enable the “term detection” mode when grabbing the Yahoo! WebPlayer code. In this case, it’s enough to merely mention a quoted movie title, and Yahoo! WebPlayer will do the rest – it will highlight the term, add a play button and then find and play the most appropriate videos for that term.

Yahoo says it will be adding support for additional media formats in the future.