I tried keybase. I find it a novelty. It's just as awful to use as pgp. So regardless of anything else it offers it's a dead end like pgp. It's designed by developers and security nerds I get it. But that's who it will stay with too.
It's not an attack on them just the reality.
People don't mind SSL because they don't have to do anything to get its benefits. It's transparent to the end user.
Is it perfect? Hell no. Managing veers is as bad as managing keys. It's a pita. But only has to be done on one end.
Even Phil Z. Learned this when he made zphone. It has to be transparent to the end user and have a simple way to authenticate the other end.
The killer is lack of good x-platform e-mail integration + difficulties in key management.
I was hoping keybase might take that on as well, but AFAIK that's not on their roadmap.