This is something that is either simply brilliant or utterly useless -- and I have no idea which is the case. I like the idea, but it needs research to see if it makes a difference. At least the developer should write some of his experiences with using this :)
I like the novelty of this. I think requiring keyboard input is distracting, though. Maybe you could just press spacebar when something appears on screen?
What's the theory/idea behind it? To me, the spacing between the numbers seemed to big to actually capture attention, but that may be the point?
I've not done any research. It's just an idea suddenly popped into my mind :-P Any comments or suggestions are welcome.
The waiting time between numbers is what requires attention.