Interesting that you say that. Coinbase is verifiably registered with FinCEN, but not the states, as far as I can see. (Square, mentioned in the article, actually is registered in California.)
If you google that address, it is an old address for earth class mail, a commercial mail scanning/forwarding service. (I use them too; they rock if you move a lot, or live overseas.)
Tradehill and Coinbase are based out of California and are following all federal and state rules.