VelEau hydration system mounts on the bike instead of the rider but I'm not sure I'd want to have that weight, though it is only 42 ounces, sloshing back and forth under me. I'm not bothered in the least by having my Camelbak on my back.
I occasionally forgo the backpack and just use a pair of water bottles in the cages and haven't had any issues in getting a drink when I needed to.
The article seems to indicate that perhaps this invention is for racing as that is when its hardest to reach down and grab a water bottle at speed. However, this unit requires going one handed to get the mouthpiece from the handlebars to one's mouth (though they do get bonus points for the mouthpiece being on a retracting cable).
I guess I'm just not seeing the real value. Maybe for those people that really are bothered by hydro packs but it should also be noted that 42 ounces is less than half the hydration I can carry in my pack.