I have a theory, but it's based on a lot of spoiler stuff that hasn't circulated around here very much. I'm waiting to see more until I start to tell anyone about where I think it will end up when Season 3 is finished.

However, I can say without any risk that I believe next season's big moment may actually be an influence on all the factions of the Island. I think it will come from an outside source, remember that someone out there was actively looking for Desmond, and was able to see his location at least once: when Oceanic 815 came down, and a day or two ago (in show time) when The Swan exploded.

Let's see where it goes...enjoy the ride!