Comment No exchange at all (Score 3, Insightful) 88
Since it's a big volume, picking one particular exchange would disturb the price of Bitcoin temporarily. That's why they decided to auction them instead. They could have sold it to the market, but to be wise the would should to sell like 10 BTC per hours unless they willing to go into [bigger] Chinese exchanges...
The beauty of bitcoin is that you don't need clearing house, exchange or bank. You can trade them directly.