They are working on faaster methods. It is now posible to identify evoked potentials associated with trying to perform a particular movement (say, move your right hand forward). Even if you are unable to actually move your hand, the brain will still produce a distinctive waveform associated with trying to move it. That can then be associated with a certain action (e.g. wheelchair moving forward). Good stuff...
/me waits for for the first Borg comment I wonder when this technology will be fast enough to operate say a robotic arm