I've a feeling that Hanso faked the crash.
I personally rule out purgatory due to the fact that people keep coming to the island, and it's not just the victims of flight 815 (Desmond, Helicopter Chick, Juliette, the Others) and the fact that all these medical miscarriages and miracles have been happening. Plus Dharma Initiative people seemed to have been coming and going to the mainland on a Submarine, and they did that Video thing for Juliette with her sister and the child in the park.
POSSIBLE SPOILER
Theory based on the commercial from next week: That's not Ben in the sack and chains. I think it's Johns father. It would only make sense that he'd want him dead, and he'd go to a criminal who's itching to strike out at Ben - Sawyer. Makes sense to me!
END POSSIBLE SPOILER
Can't wait!
Kevin