Money laundering shouldn't be a crime any more than using encryption (TLS, Truecrypt, pgp, etc) to protect your other personal data. If you're a criminal and "laundering" money, you'll eventually be caught for the crimes you're committing to make that money and that should be that. I should be allowed (and I can with Bitcoin) to hide my finances - it's nobody's business how much I have or what I do with it.