So Hurley got off the island even though it appears that he stayed behind with Locke. That would lead me to believe that Ben was also one of 'the six', and they implied that Ben would have been the one who died at the end of last season and no one attended the funeral. Remember, when Jack was asked if he was friend or family, he replied that he was neither.
It may just be me, but none of the story lines in this show have come even close to being wrapped. Whatever IT is, I want to think it is the spirit (black cloud) which killed Ecko and Walt appeared to have seen.
Speaking of Walt, Locke saw him afer being shot and left for dead by Ben. Then Locke shows up, apparently healed, and chucks a knife at Naomi.
I love this show, but I wish they would wrap up a few storylines already instead of making them deeper. After last night, it would seem that whatever the ultimate plan is, Jack had knowledge of it all along. If the goal is simply to keep everyone confused, mission accomplished. This is some highly creative writing.