Will Lost answer questions now or later?

There are rumors that Lost is planning on releasing seven seasons. I have no doubts the series can make it that far, but how will they do it? Will they keep the current questions going, or will they answer some of them and introduce an entire new premise and/or struggle? If Walt's gone the entire rest of the series, I won't be happy, and it seems like the answers are coming at us pretty fast. So the question is whether or not they can keep it going without getting redundant. I have faith in them, but one has to wonder. Just something to think about...