Well she's said Hagrid will be in all the books, so it's not Hagrid that dies next. She's also said that one of the kids will end up being a teacher at Hogwarts and that it's not Harry or Ron .. my guess is Hermione, unless she means someone else but Hermi is more fitting. So Hermione is safe .. and I can't see her killing off Ron until the last book if she plans on it .. same with Harry.
Here's an interview with her:
"Children know that a death or two will occur in the next books, and they're worried about some characters -- particularly Ron and Hagrid the groundskeeper. Do you pay attention to such concerns?"
"For five years, this was my internal world. It's still the most amazing thing to meet one person, let alone hordes of people, who knows these characters. It's heartwarming that people care enough about them to want them not to get hurt, but at the same time I have the absolute right to do what I like to my story and characters. I'm not going to write to order. I've planned the whole story, and I've always known who was going to die and who was going to come through u nscathed, and I'm not going to deviate from that."
"People love Ron, for example. Kids think you're going to knock off Ron because he's the best friend."
"Kids do, exactly, because they're sharp and they've seen so many films where the hero's best friend gets it. So they think I'm going to make it personal by killing Ron. But maybe that's a double bluff... (Laughs)"
"Now that you know they expect it, do you give it to them?"
No, I decided...It's not that I sat down with a list and decided to write, 'You're going, you're going, you're going.' There are reasons for the deaths in each case, in terms of the story. So that's why I'm doing it.
Because it's hard to draw the line here, isn't it? Because someone could read your book and say 'well, there's murder...'
"People die, but do you care when they die? Do you absolutely have a sense of how evil it is to take another person's life? Yes, I think in my book you do. I think you do. I think you see that is a horrific thing. I have enormous respect for human life. I do not think that you would read either of the deaths in that book and think, yeah, well, he's gone, off we go. Not at all. I think it's very clear where my sympathies lie. And here we are dealing with someone, I'm dealing with a villain who does hold human life incredibly cheap. That's how it happens: one squeeze of the trigger. Gone. Forever. That's evil. It's a terrible, terrible thing but you're right, I know where I draw the line. Other people will draw the line in a different place and they will disagree with me."
Is it true that you've already finished the end chapter for all your future books?
"I've written the final chapter of book seven, which was really an act of faith -- I was saying to myself, "You will get here!" It will probably need rewriting when I reach it, though."
I dunno
She might not be killing off anyone important .. it could be Draco even. I honestly have no idea but I can't see it being one of the twins, that's just me though.