User blog comment:Adam Carey/Making Ads Better: What We've Done So Far/@comment-4970747-20170118233340/@comment-20644-20170119192447

The video background is called a Video Wall and it is indeed one of the ads we offer as part of our direct ad business. Like background ads in general, that's an important part of direct ad business because Video Walls net more revenue. With that, we can remove other ad units that clutter the page.

I said this to Robin a few comments up too, but we feel that if a user has to see an ad like a Video Wall, then they shouldn't have to see seven other ads on the same page. That's a type of control we put in place this year, and we'll continue doing that this year as well. Everyone wins in that scenario: advertisers don't have to have their ads next to lower-quality programmatic ones, we bring in more revenue and can clean up the ad experience, and communities have a more premium look (no junky ads) and better page performance.

Of course, if it's moving only once every few seconds then that's a problem with the ad's performance, and we'd like to hear about that if it happens again.