Just because someone's username is Satoshi Nakamato does not mean he is the real one. I came across Bill Gates on this forum today, but I know the real Bill won't waste his time posting on forums.
The user account
satoshi is the legitimate Satoshi. For starters, he is of the rank 'Founder', is the first real account on this forum (with only an admin and hidden account before it). Combined with his post being one of the first public posts on the forum and his great knowledge of Bitcoin and the network, I would say it is safe to say he is real. Sirius and theymos could likely confirm this too, though I doubt they have the time or concern to.
But if you look at it, it's either Theymos is Satoshi, or Satoshi became really rich, vanished, changed his name and just lived somewhere where people will not recognize him.
How did you come to any of these conclusions?