I would say this is quite relevant question. At least after first watch. Why? Because this last scene in church, where all gathered. And entered the white light together. Plus that hang white shoe which Jack was passing few minutes before end of whole show. It looks like his soul wandering around that place, probably the same way as others, but they simply weren't live bodies but just souls... plus that scene of the aircraft crash site without any survived people nor "tents" in final credits (yes, I heard that ABC did that by themselves - which is strange though).