1. Jacob & the Man in Black really weren't the focus of the show after all -- it really was all about the characters we know and love.
2. The writers are postmodern Lewis fans: The Great Divorce without the "divorce" part.
3. "Live together; die alone." It is ultimately a show about caring for and helping those you love and the people around you, and then letting go.
Well done, LOST. Well done. Thanks for a fun ride.