Analysts couldn’t stop asking about video on Facebook’s third quarter earnings call Thursday. That’s because the company issued an impressive update: Facebook FB users watch eight billion videos a day, doubling the number it announced in April.

The explosive growth came from two places: The first is autoplay video, which was a tiny product tweak that Facebook launched last year. When Facebook’s 1.55 billion monthly active users scroll through their News Feeds, videos start to play automatically.

The second is Facebook’s decision to prioritize videos in News Feed. Fortune noted this in a June feature story on Facebook video:

For creators with more than a million Facebook fans, photo posts reach 14% of their audience on average, and text-only updates reach just 4%, according to one manager of content creators. But video posts? They reach 35%.

Keep in mind, eight billion daily video views is a vanity metric. YouTube (and its stars) have pushed back on Facebook’s video view count, noting that Facebook has a lower bar for what counts as a view. Any video that plays for three seconds or more counts as a view on Facebook. With autoplay starting every time a user pauses on a video, it’s easy to rack up views for videos that weren’t really watched.

YouTube counts a view as 30 seconds or more. In fact, YouTube stopped supplying total view counts in 2012, preferring instead to rely on how many hours of video people watch.

Facebook likes to tout the way News Feed fuels the discovery of new videos. “The vast majority of content is people discovering things browsing through their News Feeds,” Zuckerberg said on Thursday’s earnings call. “That’s very powerful and not something [other places] are able to do at scale in a very big way.”

Facebook has a roadmap for the ways it will enhance the video-watching experience on the site (including a big one it announced last month), he said. Deploying a favorite phrase of Facebook’s highly media-trained executives, Zuckerberg said, “It’s early days.”

Facebook has no near-term plans to host long form video content like TV shows and movies, but rather, the company hopes content producers will “chunk up their stuff” and post clips from their shows to Facebook, Zuckerberg said. He cited Jimmy Fallon’s popular Facebook videos as an example. “I’m quite excited about adding some more dimensions to video on Facebook,” he added.

Read more on Facebook video:

How Facebook’s video-traffic explosion is shaking up the advertising world

Youtube CEO: ‘Video views on Facebook are different’

Facebook’s video monetization plan is here

Facebook unrolls new tool to help video owners stop “freebooting”

Facebook will now inject videos directly into your bloodstream

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You can follow Erin Griffith on Twitter at @eringriffith, and read all of her articles here.