This scenario is really unlikely. But it would be terrible for miners, great for early adopters, and awesome for BitCoin itself. Obviously, miners would be screwed because the difficulty would go through the roof. Early adopters would be thrilled because the value of a BitCoin would go up and they could consume a very high fraction of the market volume selling off their BitCoins without causing it to crash. Not only would they get absurdly rich, but they'd be *helping* BitCoins by doing it. It would be awesome for BitCoin itself because the value of coins would go up and the involvement of large companies would legitimize BitCoins further.

The only motive I could see for them doing this would be to try to kill BitCoins. But like the Goldfinger attack, this is an absurdly inefficient way to do that.