Hi ISL,
We're totally aware that we need to be a lot more explicit and include more information on our site about the product / processes / security stuff. We've been working on this for a while now, but kind of rushed the launch due to the recent press over the NSA stuff -- we figured it was better to launch early than delay.
We're actively working on answering all those questions, and will be including a page which covers all the security aspects fully in the next week-ish.
We're 100% dedicated to making this work for our users (and ourselves), and providing real security for people.