"Maybe he's doing it wrong."
That's what I was thinking that entire video. Surely Samsung didn't create an interface that's meant to be used like that. From what I can tell, the ring is designed to do just what the digital crown is meant to on the Apple Watch; let you manipulate the interface without your finger covering the screen. However, Josh Vergara's finger spends about half of the video completely covering the watch face as it goes around and around the screen.
But it looks like he's doing it right. I've watched a few videos of people from the Samsung event using the watch and they all do the same thing. Surely a Samsung rep would have guided these journalists to use the watch as intended.
I have seen a few people use the ring in a way that doesn't cover the screen, but even then it looks like a very slow and unweildy ineraction method. I'll be interested in seeing what people think about the Gear 2 after a few weeks of use.