
With only one season remaining I think it is time to make some predictions about how
Lost is going to resolve the ridiculous mountain of unanswered (unanswerable?) questions the show has allowed to pile up over the years. As a quick refresher of what last happened in the
Lost universe, here is the Wikipedia summary of the season five finale:
In 1977, the survivors succeed in detonating the modified nuclear bomb at the construction site of the Swan station, the finale ending when the bomb is detonated. In 2007, Locke and the Others travel to the base of the four-toed statue, where Jacob lives. Locke is revealed to be an impostor: an old acquaintance of Jacob who tricks Ben into killing Jacob. In flashbacks, Jacob visits several of the main characters.
In
Lost physics the explosion of the bomb in 1977 is supposedly going to eliminate the underground source of the magnetic field so that Oceanic flight 815 will not be brought down by in the future, thereby restoring the world as it was when the main characters boarded the plane in Sydney. I have a really major problem with this logic: changing an event in 1977 alters which
of the potential futures becomes reality from that moment onward--that is, everything from that moment forward represents a different future from the one that occurred without the explosion. Here's a rough idea of what I mean:

I guess my main point is just that detonating that bomb ensures that it is not possible for the future to turn out the way it already has--expressed another way, the future that we, the viewers, have already seen cannot possibly be repeated. We have jumped from one potential future to another in which the plane cannot crash because of the magnetic field, even if everyone is on the plane as they were in the future we already know (this all assumes that Faraday's belief that the detonation will destroy the magnetic field is correct).
All that said, I think one of the consistent themes throughout the show has been the inevitability of the role each person plays. In the end all those who are 'supposed to be on the island' will be there whether the plane crashes or not; Jack will become de facto leader; Sawyer will initially rebel but become respectable when need be; Ben will connive and backstab; et cetera. This seems to imply that we should be able to piece together the basic point of the show--if everyone will fill the same role throughout this alternate future then the moral will be the same. Before I go off on another long ramble I'll ask a few questions of the floor: Is my reasoning sound? What do you think of differently? What is the moral of the show? How is Jacob's old friend inhabiting Locke's body? (I didn't even bother to touch on this just yet.)
Oh, and here's a barely-related GraphJam post that I enjoyed: