I might be wrong, but it wasn't returned, but that doesn't matter, all the mining ops switched to the 0.7 chain, and the transaction is now in limbo (for lack of a better term); the forked 0.8 chain.
He paid it back, he said something about it in the irc channel this morning.
Still, it's an exploitable vulnerability. Very difficult to make the conditions happen, but if they happen naturally it's something that can be taken advantage of. It'll need to be addressed in one way or another.
The guy used a $10,000 double spend to publicly extort OKPay to expedite a smaller refund, rather than go through support. I'm not sure I'd be very gracious either, or ever do business with this guy again.
I got the impression he had tried to go through support, and got no response until he ended up with $10,000 of their money. Then all of a sudden, they solved his problem.
But if it happened like you think, I definitely agree with you.
