A friend just sent me this link to a blog entry that describes the return of GPG Mail to Snow Leopard 10.6.2:

http://carlton.oriley.net/blog/?p=20

The link to the download is:

http://carlton.oriley.net/blog/wp-content/uploads/2009/12/GPGMail-1.2.1.mailbundle.zip

And it works! Go get it.