However, I am pointing out something that a lot of non-US citizens on HN have been saying lots over the past few weeks; setting up an email service that is outside the US (for the purpose of trying to avoid PRISM surveillance) is nontrivial, and while it would be great if this app were the answer to that, it sadly isn't.
I'm all for the US justice system doing what it's supposed to and having the supreme court rule on the constitutionality of PRISM! Then it will no longer be valid to generalise that all US-hosted services are bad news for privacy.
On the other hand, if you have specific counterparties and you can get them to switch to the same thing you're using, just use TorMail, or run a VPS somewhere where you both have SSH keys and use it as a dead-drop, or whatever. "The solution must involve SMTP and POP/IMAP" is only relevant when you're communicating with unauthenticated peers... at which point, you'd better not say anything important anyway. ;)
If noone is standing up for the constitution anymore, then the legislature + executive have taken control.