For:
It does sound VERY like a live recording. Turn the volume way up and you can hear the notes being pressed before the sound.
It could just be a piano synth. I've heard results this good from the Reason piano bank and that Grand sound font VST thingy.
Against:
If you were THAT good at piano, would you lower yourself to use 'a cool piece' to describe it?
The comment dosn't actually suggest he made it at all
Lack of static, recording quality is the sort of thing you would find on a soundtrack CD
It's amazingly composed and performed, and most of the classical authors on the AP would struggle to get a track out like that.
I'm not going to flag it for now but looking at the way all his other tracks are from games like final fantasy, it seems more and more likely he ripped it from the game. Somebody must know the tune, right?