Okay...At this point, I don't think that I would be able to accept a single transaction from a single early block as enough evidence because that doesn't rule out, albeit a very tiny, possibility that a private key was somehow brute forced by a couple super computers fully dedicated to the task.
I want to see a transaction from block #1 to block #9 and from block #9 back to block #1. This would at least establish that more than one private key, known to be generated by Satoshi Nakamoto, is in play. It would increase the weight of the evidence, and reduce the likelihood that the keys were somehow hacked into existence.
I like this standard of proof. It seems reasonable and raises the bar for would be bad actor-impersonators.
To be sure, there's too much funny stuff going on in this space so a single transaction from an early block would no longer be sufficient validation in my mind. It will require a compound transaction to add extra layer of validation to convince me now. It's the only way to negate, in my mind, the negative credibility created by all the apparent "trickery" that's been exposed to date.
Furthermore, the above would only prove to me that Wright holds the private keys to Satoshi's stake, not that he is, in fact, Satoshi. That's where Gavin's assessment comes into play here. If Wright proves he holds the keys && if others confirm that Wright is privy to information only contained within private communications between themselves and Satoshi Nakamoto, then maybe Wright might be justified in having the opportunity to turn down his Nobel Prize like his idol, Jean-Paul Sartre.
.... still do not believe this guy is anywhere near who Satoshi is or was. 