So, possible scenarios:
1. Satoshi is a group of people. Subscenario 1: Founded by some powerful entity, to create an experiment or destroy banking system. Or make drug trafficking easier.
2. Satoshi is dead. He didn't really knew that bitcoin might have such success, he died before seeing it growing so much and that's all.
Subcenario 1: Satoshi was killed because of Bitcoin.
3. Satoshi is affraid of Bitcoin and how it turned up.
4. Satoshi is a person that has no life other than programming (21.000.000% nerd) and he creates things under different identities. Maybe was behind Napster too.
5. Satoshi is ET or AI or GOD or S8TN
I also think a lot about this topic and directly about Satoshi Nakamoto. Out of 5 possible options, I like it better 5. Let this scenario be more fantastic, but for some reason I believe in this one.I think it's the most powerful artificial intelligence,which can and has created a 1 person or group of people,but at the moment it develops itself.