I think that Iceman has always been an interesting character, especially in Ultimate. He's a realisitic teenager... He doesn't take too many things seriously, there's an edge to him that reeks of immaturity, there's that whole "nothing can happen to me" mentality, there's humor and sarcasm in his dialogue even in the most serious situations, and he holds his friends closer to heart than his family. I think that Millar and Vaughan (Yes, I'm exlcluding Bendis) did a wonderful job showing all of this and it only seems to be getting better with Iceman!