After the Gox dabatase leak the names and home addresses of pretty much everybody involved in BTC are now public, at least among the criminal community.

Those singing the song that goes "I don't mix my coins because I have nothing to hide" are either:

a) totally brainwashed/incredibly naive
b) just stupid.

Even if you mined the vast majority of your coins and used an exchange just to cash out a minor part of your holdings, your total BTC balance can be discovered by trivial blockchain analysis, following the links with just one deposit/withdrawal address.

Morale of the story: Everybody should ALWAYS mix their coins and use Tor for BTC related activities. Information is power. Never give it away.