Our main source is a commentary in Weiqi Tiandi [World of Go] by Zhang Wenyong, but we are concerned here with just one part. The rest is worth looking at, however (and, as we have said before, so is the rest of the magazine - it seems to stand above all others at present, at least for stronger players).
Zhang collaborated mainly with the winner, Qiu Jun, but also spoke to Wang Lei 8-dan and, eventually, to Gu Li. It seems that Qiu Jun in the end not only had the benefit of a mistake by Gu, but was also lucky that his own mistake was not exposed. (Qiu has been a tough rival for Gu, and in general seems to get into more than his fair share of torturously complex games.)
The critical position for us is when White, Gu Li, played 238, as marked. This was the mistake. Gu himself realised soon after what he should done, but he was misled by a miscalculation. The winning line did involve messy kos and depended on having just one extra ko threat, but he had a time advantage anyway. Qiu was down to his last ten minutes, though he could buy extra time for 2 points a time under Ing rules (this seems to happen quite a lot by the way - the basic allowance is three hours each).
Note that Black and White each have a large unalive group entwined with each other in a capturing race running from the bottom centre to the centre right. There are three kos within this fight. There is also a fourth ko at the top which you can ignore for the time being.
We will not be looking at the rest of the game, but if you wish to see it
through you can download it here 
.
Qiu Jun apparently looked at Gu Li's move with incredulity, but (according to
Zhang) instantly connected at A like a drowning man clutching at straws.
The actual game continued with an ordinary ko fight up to move 283 before
Gu Li resigned, having saved the group at the top right by way of ko threats,
but having lost the big group on the centre right.