Hey,

Anyone ever find out what it was?

no one knows yet...

but those with Xbox Live for windows were able to look at one of the profile files and found an achievement for beating the entire game on hard without using a vita-station..

I'm really hoping that's NOT the achievement because that would be really boring/suck. (you'd basically just have to reload your save ever time you were about to die)

There are some that speculate that is not the achievement because it's one of a few achievements that were originally planned for the game but dropped, and they think maybe it's just some left-over code that was never removed and not actually the new achievement.

I'm hoping it's related to some new content.