I think, eventually, this kind of tech and motion control could be used in concert. The brain interface would not be used to replace a person's functioning limbs, but for things impossible outside the world of the game, such as magic... sorta like what Rex Dark was getting at. Given that, as well as the possibilities this brings to disabled gamers, I give this advancement two thumbs up.
Also, for everyone afraid of this being used for mind control, this kind of system only has the ability to detect input FROM the brain. Someone would have to design a system that could output signals TO the brain, AND get people to buy it. This means the feature would either have to be added in secret and covered up, or have a good advertising campaign with an insane amount of positive spin towards the capabilities such a feature (combined with consumer stupidity/unawareness).