If I recall correctly, it is difficult to transfer dollars in there from the bank.
Sorry to clarify, do you mean USD cash into MtGOX is restricted in some sense?
If so, the clients cannot convert USD to BTC and no fiat issue there. Am I missing something?
Oh, yes, I worded that incorrectly.
It is difficult to move dollars from your personal bank account to a bitcoin exchange. At least, this was the case in December. The point was this statement's truth would imply a constant shortage of dollars and would lead to the depreciation of the value of all cryptocurrencies.