On the Twitter video side, some "select publishers" will actually have access to 10-minute videos, so don't be surprised if you start seeing entire John Oliver segments popping up in your timeline. The longer video clips come with their very own fullscreen viewing mode, similar to what Facebook and YouTube's mobile apps already offer.
As for Vine, the standalone app will now offer some content creators the ability to link their traditional six-second clips to longer videos with a "Watch more" button in the lower right corner. These longform Vines, as it were, also open up the canvas to full, widescreen videos and not just the vertical, square crop we've gotten used to. And a new feature is getting carried over from Periscope as well: double tapping a video now makes hearts fly over the screen.
Finally, because all of this is obviously in service of the almighty ad dollar, Twitter says the company will be expanding the monetization options they rolled out through Open Amplify last year. And, if you're already famous, Twitter is rolling out a new app called Engage today, which should help you interact with all your rabid fans.