One of the people who the O6 say has died has got to have some sort of significance to the central players in the game surrounding the Island. There's some kind of competition going on, either to harness the forces of the Island, or to destroy it. Once it's found by one side or the other, the game's up and the fate of the world as we know it is sealed.

I envision that one side (light or dark, you decide) intends to destroy the Island, which will ultimately lead to the destruction of our world (our timeline, our consciousness as it is now). The other side will find the Island and use it for its own benefit...which will ultimately change the timeline too, thus altering our consciousness.

I imagine that whoever Adam and Eve turn out to be, will be the individuals who ultimately sacrifice themselves in order to prevent either the "light" or the "dark" outcome.

PS, I have my own theory about Adam and Eve. I think it's Rose and Bernard.