It would be nice if AlphaGo emitted the estimated probability of it winning every time a move is made. I wonder what this curve looks like. I would imagine mistakes by the human opponent would give nice little jumps in the curve. If the commentary is correct, we would expect very high probability 40-60 minutes into the game. Perhaps something crushing, like 99,9%
For me, the key moment came when I saw Hassabis passing his iPhone to other Google executives in our VIP room, some three hours into the game. From their smiles, you knew straight away that they were pretty sure they were winning – although the experts providing the live public commentary on the match that was broadcast to our room weren’t clear on the matter, and remained confused up to the end of the game just before Lee resigned. (I'm told that other high-level commentators did see the writing on the wall, however).