One of the best things Satoshi did was to invent bitcoin. Even better was that he disassociated himself from it. I strongly believe Satoshi is out there, alive and well, however the chances that he surfaces are slim to none. It's for the good of bitcoin. Satoshi has done his job well.
If he doesn't distance himself from bitcoin and give full power to the community. No matter how great bitcoin is, if it still depends on him, it will not be able to attract attention and become as great as it is today.
I don't know but I hope and pray he is still alive and will use his 1 million BTC one day. Many people are worried that he will sell all his bitcoins and cause panic in the market but in my opinion he deserves it for his contributions.