My guess is that if this isn't Zelda that this game might be Link's earliest incarnation and the one that finally explains how he got roped into the conflict between Hylia and Demise from Skyward Sword. I couldn't be the only person playing SS and thinking to themselves that Link's ancestors did something royally stupid to be cursed with helping the Goddess out until the end of time.

I do think this game looks to be an earlier installment in the timeline. The Bow and Arrow look a bit Magitek to me and that monster they fight looks like a machine that plants have grown over. I'm thinking this game will predate Skyward Sword in the timeline.

I still feel that the video is mostly a concept trailer but if they can get that kind of seamless transitions of enemy encounters and environmental destruction and promise a more open ended approach similar to the original Zelda, I think we're all in for a treat with this one.