A strange invitation from Facebook (NASDAQ: FB) announced that the social network would announce a new product Thursday, June 20, at its Menlo Park, Calif., headquarters. While information on this product is limited, many expect that Facebook will introduce a video version of Instagram that allows users to capture and share short video clips.

“A small team has been working on a big idea,” the Facebook invitation said. “Join us for coffee and learn about a new product.”

A video version of Vine would make sense for Facebook to stay in competition with Twitter, whose Vine app, sometimes called “Instagram for video,” has exploded in popularity. Vine gained mainstream awareness after it was used to capture footage from the Boston Marathon bombings, and shares of Vine video have surpassed shares of Instagram pictures since Twitter released a version of the app for Android in early June.

Vine Shares Surpassed Instagram
Since Twitter released Vine for Android, shares have surpassed those of Instagram. Marketing Land

Matthew Keys wrote that Facebook was internally testing a Vine-like version of Instagram nearly a month ago. It allowed users to capture and upload five to 10 second videos, but other Instagram functionality specifics like filters were unknown.

Facebook could release a stand-alone video app, but it would make more sense for it to update Instagram to include video. Since Facebook bought Instagram almost a year ago for about $1 billion, the social photo app has grown to more than 100 million active monthly users. It would give users another reason to visit Instagram and take pressure off of users to download a new app and build up yet another social network.

After all, Facebook's primary revenue comes from advertising. Although Instagram doesn't yet feature advertisements, many brands use it to reach customers. Many advertisers have found creative ways to use Vine and will surely use video to reach those 100 million users on Instagram.

Facebook has taken great lengths to keep the details of the event secret. Invitations to the event were sent via snail mail on white, coffee-stained paper. TechCrunch points out that the invitation could be a red herring. Facebook could actually reveal a news-reading app, or something completely different.

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