I agree that everyone should read this.
So, assuming the one 'user' with 500k BTC was MagicalTux, or someone close to him:
1) Gox launches with swiss cheese for security
2) Gox ignores all warning about being vulnerable, and continues to tell users they're safe
3) Gox gets hacked
4) Magical Tux's BTC gets sold for pennies
5) Magical Tux wants to roll back the transactions to get his bitcoin back
Am I missing something?
Magical Tux probably doesn't have 500k BTC. Perhaps everyone on the site
combined would add up to 500k BTC. I think every bitcoin on the site got liquidated. So he is backing it out. The problem is whether the coins got transferred out before he caught the transaction.