GPG (aka PGP) is secure but it's difficult to use. Unfortunately the people who need it the most are also the people who have the hardest time figuring out how to use it. Namely lawyers, doctors, political activists, etc. End-to-end encryption systems only work if both parties use the technology properly. That's why I'm pushing for the creation of a secure, easy-to-use system that I hope will become ubiquitous. A system that encourages migration by heaping shame on those who haven't made the switch.
Other encryption technologies I trust would be voip calls using ZRTP and instant messaging sessions protected by OTR. Of course both technologies still require the users to check the fingerprints. How many people do that?
The bottom line is this: I trust the cryptographic primitives. What's trickier is deciding which protocols and implementations to trust. Figuring that out is a full time job.