Just watch... If I talk, it'll ruin the surprise ;)

Yup, that's a dude... and he's singing BOTH parts! Watching a female sound come out of that guy is pretty nuts all by itself, but what I'm curious about is how he even got the idea to TRY her vocal in the first place! Either way, this video made him an instant YouTube sensation and now he ironically works for Disney/Pixar as a 3D modeling animator! Who knew?