I believe that actually Kevin doesn't have to give back any of it.
He purchased them in good faith. Even if the market was crashing, I would have purchased it if I saw the opportunity.
- Now, even if it is on his right to keep them, IF the money belonged to MTGOX (and not a user, but actually the main fund of MTGOX, which seems to be more plausible the more I think) then I guess that for the betterment of the economy and its stability, Kevin should give it back to MtGoX.
In exchange of the devolution, MtGox should give a compensation for the act of good faith and allow Kevin to keep the withdrawn amount - If the account was a personal one, Kevin has less obligation to give it back to the owner of it. When you make the wrong call playing poker you can't undo it, if you fucked it up, you fucked it up. Period.
But still, it would be a nice gesture, and this would be totally from Kevin's generosity, if Kevin gives back partially or totally to the previous owner. A generous compensation for this gesture would be appropriate.
BUT, Kevin has all the rights to keep it and not giving it back to anyone. He would be a total asshole by behaving like that, but it is in his right.
Now, everything depends on his will.
MtGox shouldn't rollback shit.
The least thing that MtGox can do is to compensate to all users for this scandal and for they negligence/incompetence.
The leaked userbase is embarrassing enough, and that needs a fair compensation to all of us who entrusted this site with our money, and in some cases, our life savings (doesn't matter if trusting one's savings is a unsound judgement, the point here is that our trust has been broken).
It takes decades to build trust, and only one second to break it.
Usually, one never recovers full trust with a person, but doing good deeds can help to reestablish the relationship.
I hope MtGox understands here that more than profit, trust is actually the backbone of a business.
If you don't offer a deal to keep your users happy, expect a bank run.
(Wrong thread, I wanted to post it in Kevin's thread...)
Kevin has no right to keep ANY of it if it's PROVEN that there was a hacker that facilitated the price dropping to $0.01 with someone else's account (even if he wasn't involved at all), people forget here that there is one person in this scenario that is more likely (way more likely) to make a considerable amount of money in the long run with bitcoins and it's not Kevin, so why would this Magic Tux dude stick a fork in his cash cow...? Kevin, OTOH...? he is much less likely to make a considerable amount of money with bitcoins in the long run, if you honestly think he can make as much or more money as a trader than a major exchange (THE major exchange before all this hit the fan) then I don't know what to tell you because you live in a fantasy world, Tux can run a legitimate business and make money hand over fist, Kevin needs something like what just happened to "make out like a bandit" and run with his cash...