That partially answers the question about the early adopters holding most of the bitcoins. The original programmer cashed out in 2011. That still does not prove he is Satoshi Nakamoto, but he probably knows who he is.
Another lead:
Investigations into the real identity of Satoshi Nakamoto have been attempted by The New Yorker and Fast Company. Fast Company's investigation brought up circumstantial evidence that indicated a link between a encryption patent filed by Neal King, Vladimir Oksman and Charles Bry on August 15, 2008 and the bitcoin.org domain name which was registered 72 hours later. The patent (#20100042841) contained networking and encryption technologies similar to bitcoin's. After textual analysis, the phrase "...computationally impractical to reverse." was found in both the patent application and bitcoin's whitepaper.[1] All three inventors explicitly denied being Satoshi Nakamoto.[17][18]...
https://en.wikipedia.org/wiki/Bitcoin