It sure sounds great but I would not call it 'pitch correction'. His voice is way too far off pitch.
In my view the following takes place :
There is a midifile playing, midi melodyline is used for setting the right pitch, independent from what note he is actually singing.
With his left hand fingers the next melody note is started. (single step trigger)

I expect this feature will be only available for midifile 'players' ;-)