I get the impression that Google has been putting a lot of resources into GAE all this time, but mostly into retiring technical debt and integrating it with the new expansive "cloud platform" vision. I also get the impression that nothing happens quickly in Google-land :-(
That said, even "as-is" without any major changes on the horizon, GAE is pretty solid. My only major complaint right now is Java8, but given the choice between suffering with Java7 for another year and hiring an ops staff, I'll pick the former. I had to make "the platform" choice again just a couple weeks ago for a new startup, and still picked old-style GAE - not even the new Managed VMs, which I don't think are reliable enough yet.
Naked domains aren't an itch of mine, apparently.