Jeff Garzik, a member of the Bitcoin core development team, says in an email that bitcoin is not as anonymous as the denizens of Silk Road would like to believe. He explains that because all Bitcoin transactions are recorded in a public log, though the identities of all the parties are anonymous, law enforcement could use sophisticated network analysis techniques to parse the transaction flow and track down individual Bitcoin users.

"Attempting major illicit transactions with bitcoin, given existing statistical analysis techniques deployed in the field by law enforcement, is pretty damned dumb," he says.