I've thought about who will die, and I think Sakura seems most likely to die. Let's face it, only one of these characters can end up with Naruto. It's either Sakura or Hinata that must die. Sai is also a prime candidate for death, since Sasuke returning makes Sai quite worthless now.
But I think the character most likely to die is Kiba. He's obnoxious, lame and general a little hater. Though I'd rather have Rock Lee die, I think it's unlikely.