Have to fangirl once I saw this video. I love Classical music. In the car, our family listens to the classical music channel on the radio, and tries to identify composers based on the music alone.
And we've got piano roots, so I can definitely appreciate this stuff. I actually did Adagio Cantabile in the way back when, but I dropped piano for percussion.

(Except the piano they used on Chocolate was TERRIBLE. It muted all of the playing, so there was barely any depth to the sound, especially the important bass line. It wasn't even tuned that well.

)
But I digress. My sister briefly attempted this one, before she dropped piano for violin (

), so I know what bitch it is to play. Chopin is always crazy(but sounds AWESOME). You've got the left hand playing in six, while the right hand plays in eight (but only seven notes of it

). I can handle three and two at the same time, and even switch between six and eight, but I definitely can't handle six and eight on separate hands, at the same time. (and this without taking different pitches into account)
[SNSD] Seo Hyun playing piano "Fantasy Impromptu - Chopin" - 서현 소녀시대 피아노 