The day you've been waiting for is finally here. You can now post GIFs on Facebook thanks to a workaround from Giphy.
Basically, Giphy (a search engine for GIFs), created a code that makes GIFs actually loop on Facebook. It works simply like posting a link to a video. Either copy paste the URL of the page for the GIF you've selected, or embed straight to Facebook from that page from the portion where it says "share GIF". It will look just like a video upload to your Facebook wall or Newsfeed, in that you'll see a play button on the embed. When you press play, presto! You have a GIF. The only stipulation is the URL must come from Giphy. But, who cares, GIFs on Facebook are finally here. [Giphy]
Update 1: The excitement over Facebook GIFs seems to have crashed Giphy's site. So hang onto your best reaction GIFs in the downtime. We'll let you know when it's back.
Update 2: Giphy is back, but it might be a little slow.
Update 3: Facebook spokesperson reached out to say that "Facebook does not support animated GIFs." So for the record, Facebook doesn't officially support GIFs, but Giphy links work like GIFs on Facebook, nonetheless.