I do think that Harry will be killing more than one person before Voltemort. Because he needs to get a taste of what killing does to you before he faces Voltemort. i think that is one of the issue's J.K Rowling will give Harry to deal with in book seven. It will likely be too late in the story to have any insight to how he feels about taking a life when he kills Voldemort. So I think he will kill a Deatheater or two before he faces Voltemort. It is no easy feat, to take a life (I am saying that purely on a theoretic basis', I assure you

What do you think on this?