You have to applaud them, they are fucking brave. I absolutely love them for it!! If it works then they will revolutionise the industry, if people dont take to it, well Im sure the Rev will be even more niche than the cube, but well still love it (Oh, ill also lose even more faith with the general public).
Just imagine Mario Kart, controlling the movement with your hand, hold onto the B trigger to go into a slide and you have to jerk your hand to do the slide turbo - great stuff!!
I also know someone with one arm who has always wanted to play games, there was a one handed controller once but it was shit.