Google began testing video ads with partner Viacom today.

The initial test, which will include up to 150 AdSense members selected by Google, will use channels of video content provided by MTV Networks and will last four weeks. The testers received instructions on how to implement a JavaScript object that embeds a Flash player in their Web sites. You can view a sample video advertisement here.

"Google is running an experiment with syndicated video supported by ads, to help publishers and video content owners better monetize their properties," read an e-mail to one AdSense partner. "Premium video owners provide Google with their content, Google matches the content with ads, and the site owner presents the combined product to their users."

Publishers will earn revenue with these ads on a CPM basis by the number of views of each ad inside the content. The Flash player will not play ads unless a user clicks on it. The revenue is split three ways between Google, the publisher and Viacom. Google is not disclosing the split during the test, perhaps because the ratio will change based on performance.

Google stipulates that testers must place the ad (IAB 336x280 & IAB 300x250) above the fold on their sites, and each page may only have one ad. Google says the content is expected to change every three to seven days.