OK, got it.
Another dumb question then... do I simply enter my name and shipping address, enter my PIN and that automatically encrypts my name/address?
No, your details are not automatically encrypted - they're encrypted on the server so anyone that might have access to them won't be able to see them but they are not encrypted on the vendor's end; you will have to encrypt them using PGP, and guides for this are available all over the forum, particularly in the Newbie discussion and Security forums.
Libertas
Of course it's a good idea to encrypt your info, but out of curiosity: Has there been any cases of a vendor getting investigated, the police finding sales records, and the customers actually getting charged with anything? I've never heard of such a thing happening despite tons of vendors with zero encryption getting busted before SR.
Not as far as I'm aware, but perhaps that is because the people who could report it are either going through the court system and thought better than logging in to Silk Road and the forums or possibly they are in prison already. Then again, perhaps nothing happened to them - we just don't know.
Regardless, that is no reason to become complacent. It takes under 5 seconds to encrypt an address and copy & paste it into the address field when placing an order. Is 5 seconds really worth the less than desirable possibilities that can result from not spending that time using PGP?
Libetas