I'm assuming you mean those who think Israel has been replaced by those in the church age? I don't believe this as it goes completely against a host of scripture otherwise...and I have looked carefully at their point of view. There are so many holes in their, shall I say, theory. But I was willing to investigate replacement theology, as it is sometimes referred as. To me it's rather like the differences between Creationism and Evolution...it's that broad of a difference but people will argue it to the point of almost death.
I was once taught by a woman who believed that...she was very strong in the things of God and I admire her to this day, but we do part company on this issue. Our debates proved interesting as she actually began to question what she has believed for many years.