We need to see it used with games in every genre out there.
So far, it looks okay. It does show it is leagues ahead of using silly analog sticks in a first person shooter. The guy even mentions how you don't need autoaim anymore (you scrubs). You don't have to "guess" with sticks, you can pretty much go exactly where you want to aim.
But we must see how it performs with other games. Yeah, we've heard it'll do Spelunky and Super Meat Boy just fine, which is a superb baseline for 2D platformers. Though what about 3D platformers, like Sonic Generations or A Hat in Time?
What about fighting games? Driving games? Puzzlers? Various RPGs like Deus Ex or Baldur's Gate? Can users come up with viable configurations since there are going to be user-made control bindings distributed through the Steam Workshop?
There's lots of unknowns. The potential for this is looking good for now, at least.