Instagram Video has been catching on like wildfire since its debut Thursday, tearing into the social video market that had previously been dominated by Twitter's Vine app. It makes sense that Instagram's one-click-and-you're-suddenly-artsy appeal would do well on video. And Instagram, which is owned by Facebook, was wise to roll out the feature now, just as the number of Vine shares on Twitter inched forward to surpass daily shared Instagram photos. 

The great thing about Instagram Video is that you really don't need to download anything new. The only change you'll notice on the previously-installed Instagram app is a tiny new movie icon that will take you into video mode. From there, you can take 3-15 second videos — an upgrade from Vine's max 6-seconds — then process them with one of 13 filters and share immediately. If you're curious as to how that might look, here's the first video that made it to 1 million views (watch at your own risk…).

It will be interesting to see how this will impact the Facebook/Twitter rivalry long-term. One thing is for certain: Twitter has felt the heat these past four days, with Vine dropping from #2 to #7 on the U.S. iPhone download chart of free apps between Thursday and Sunday.

Which do you prefer: Instagram Video or Vine?