I think it's none of the above and probably nobody we've even suspected. He's probably just some random geek who came up with a great idea and just put it out into the world.
Add Tatsuaki Okamoto on the poll
Tatsuaki Okamoto out of the suggested people definitely has the best chances so far to be Satoshi, there are a whole lot of similarities.
Like what? I think the name is far too similar. No point using an alias like this.