[fryke]

There's still MacGPG (the GNU version of PGP, I think, in some way). It has a Mail.app plugin afaik. But as I've said: I've never used it... :/

Here's a call: Apple should make security REALLY easy to grasp, i.e.: On first opening Mail.app, it should ask you whether you want to use GPG (or their S/MIME, whatever) and then create everything for you (asking for passphrases and random input etc., of course for security reasons). After that you'd be set up and can publish your public key. But hey, what do I know...