[pemulis]

Actually, bitcoins being classified as securities might make it easier for governments to crack down on them: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1817857

Securities are more closely regulated than commodities in the US. I'm not sure what the laws are in Japan, where Mt. Gox is located, but I expect they could find some legal pretense to raid the exchange. There may be more exchanges popping up all the time, but almost everyone uses Mt. Gox. As a result, they're holding a huge amount of bitcoins and digital cash. That makes it a major target for a raid.

I wonder if they will start keeping backup servers in multiple countries, like Wikileaks? I'm not sure if that would protect peoples' digital cash, but their bitcoins would be safe in the event of a raid on the main server.

[maurice]

Hm, what do you mean by 'main server'?

[pemulis]

Wherever Mt. Gox is storing people's bitcoins (the exchange's wallet.dat) and their deposits in USD and EUR, as well as wherever trades, deposits, and - especially - withdrawals are processed. Lots of people have large non-bitcoin deposits in the exchange, and if a raid on a small number of locations in Japan can prevent them from withdrawing or result in their money being seized, that's a serious issue for the bitcoin project as a whole.

Edit: Also, it looks like Mutum Sigillum LLC, the company that processes Mt. Gox's deposits and withdrawals through Dwolla, is incorporated in Delaware. I wonder if they process those transactions in the US?