The OST is really great. Some songs have singing, but so far, it's been fine. Haven't heard the metal chocobo thing in-game yet. I heard it on youtube, and it's so bad, it's hilarious.
The game is awesome by the way. I've played about 3 hours. You can save anywhere, they got rid of the pointless weapon upgrade system (now, you just buy new weapons to get stronger, like most other RPGs out there), and the battles are a bit faster and more intense. The Crystarium looks very different, but I'm not sure how different it really is structurally/functionally. Still trying to work it out.