Well, now they've enhanced that so you can send the post and sign it via PGP/GPG and don't need to send your PIN in cleartext when making a post. That is really cool. And they publish your PGP/GPG public key for you, too. Mine, for example, is here.
They've also added other cool things like being able to post via a phone call, which I may test out later. Information about all the cool stuff they've added can be found in this post in

Edit: OK, that was cool. They even seem to have fixed what I saw was an annoying word-wrap problem of hard breaks showing up in the post that was from an email message. I'm impressed.