Video advertisements are coming to Facebook. 

On Tuesday, the social media giant announced that it will start selling video advertisements. The new ads will appear in users' newsfeeds as early as Thursday. Although it is unclear how long the videos will be, they will play automatically without sound in users’ feeds on both the Web and Facebook's mobile app. The social media site tested the video ad technology last week, so some Facebook users have already experienced the new ad format, The Wall Street Journal reported.

Facebook had previously planned to incorporate video ads into its advertising model starting as early as the summer. The Journal reported that some companies even had video ads ready for the holiday season in anticipation. Right now the only ad running on the site is for the Lion's Gate movie Divergent, but as more marketers get on board, the way companies interact with consumers on the social media site will undoubtedly change. 

"Facebook has seen the revenue success that YouTube is having with video ads--$5.6 Billion in 2013--and is looking to diversify their revenue by adding video. They want to compete directly with YouTube," said Kipp Bodnar, vice president of marketing at HubSpot, a Cambridge, Massachusetts-based marketing firm. "The video ad unit is targeted at predominately larger companies who already have video production and TV spots baked into their marketing strategy. That being said, you will also likely see some video savvy small business take advantage of this change as well."

Video ads could be a boon for marketers, but there is the concern that the format will annoy and alienate Facebook users and potential customers. "Consumers are used to the ad-supported model online, but the risk is in how they plan to implement the ad units themselves," said Bodnar. 

Ads playing in newsfeeds automatically might be the biggest concern, Bodnar added. "While this is great for Facebook because it will create greater inventory for video ads, I am not sure it is the best thing for the end user. This is a significant change to the newsfeed user experience and any change like this is often met with a backlash," he said. 

Facebook has not yet disclosed how much the video ads will cost. In August, the Journal reported that Facebook planned to charge advertisers $2 million per day to reach the full Facebook audience of users ages 18-54. Additionally, Facebook stressed that the videos will not eat up data plans on mobile devices but will be downloaded ahead of time when devices are connected to a Wi-Fi network.