Yeah, worth watching the video. The music accompaniment was terrible and louder than it should be, but the concept is nice.
In the end of the video, they show it where the trackpad would be, which makes me think there might be a size issue. They also show it with a regular keyboard and I'm not sure everyone would require one. I do know that people like tactile keyboards but some folks have managed to function without one. So, a model where the touchpad is also the keyboard might be cool.
I touch-type, but maybe the trackpad could also be some sort of secondary display? I could see that coming in handy, perhaps even to display the above mentioned keyboard for this who can't touch-type.
Off-topic: HN is one of the few sites where I regularly click on links in the comments. On most sites, that's not a very productive activity. On HN, it is often interesting and educational.