If you're an interface designer (I am), you should pre-order this thing. This will be a standard form of interaction in a couple of years and you should jump on it early and start figuring out the kinks. Too cool.
There are so many use cases where it doesn't even work that would require a complete rethink of how anything is presented on in internet. For example how about the HN comments where it's pasted as code and it scrolls horizontally. Target that and scroll it with that system. As soon as you have a single use case where a mouse and keyboard is more effective you blow your value.