Gaga isn't precious about who she refers to as "a friend", but obviously there's SOME sort of relationship between them. She wouldn't refer to him as "a friend" if all they'd had was a twitter exchange. Come on.
But yeah, I think a collab could be on the cards here. She compliments his song, then they become friendly?
Have to agree with her, I didn't fancy a collab between them until LOOH - which is great. That kind of throwback-but-current sound would work well if her next album is disco flavoured.