It's definitely a neat concept, I just wonder if it's all talk, or will actually catch on and go anywhere.
The lag concerns seem to be primary here, considering you're potentially adding upwards of 100-200ms(roundtrip) of time to each keystroke. It could very well render games unplayable, but I guess they feel confident that they've worked out the kinks otherwise they wouldn't be talking about it.
The only teeth strong enough to eat other teeth.