Okay that's good! On my app, the preview only shows a landscape portion of the portrait video, which cuts out most of it, buuuut it looks fine when you click on it! So I guess I just need to get into the habit of clicking on videos rather than letting them play on the preview pane like on Twitter

Ah yeah, I keep autoplaying videos off. Less distracting that way. ^^ Hopefully the team will update the preview to match the aspect ratio soon.