We are in full agreement. Parley.co does not use Javascript crypto or browser plugins, ie. it is not webmail. (There is a webmail component that can be used to send messages which are encrypted at the server, and can allow synchronous two-way communications for logged in Parley users that is not end-to-end, but it is only provided as a stop-gap and the trade-offs are clearly presented. Discussing it usually ends up as a distraction, since our core offering is based on installing standalone clients.)

We'll be posting more information about the whole thing soon, but if anyone has any questions I'm always happy to discuss what we're doing either by email (in my profile) or (at risk of derailing the thread) here.

EDIT: Also, Parley uses OpenPGP. People who are happy with their PGP/GPG setup should continue using it, but the goal is to create a compatible service which those people would feel comfortable recommending to less tech-savvy friends.

Don't blame subpoenas for the problem of spineless admins that will actively hack their clients because the government asked them to. Backdoors can't be mandated by a subpoena, only the recording of server-side data (unless I am grossly misinformed).