Skills don’t have to be in the Echo app first in order for other people to be able to use them. Those are just featured skills.
Look at the work @zpriddy has already done, and he has multiple other people using it. This is not a hack using the Hue emulator. He is using the official Amazon skills kit.
So yes, Amazon has to know something about it, but not a full-scale announcement nor does it have to show up in the echo app first to be usable by others.
As far as direct integration as a “connected device” goes, that would be fantastic. I just don’t know if that’s what we’re getting. The blog post that was pulled had a headline that said something like “Alexa, tell smartthings…” Which is the way zpriddy’s works.
And “connected devices” is yet another category from skills or featured skills. That’s the one where you can put things into groups through the echo app, and you don’t need to do the “tell…” Step. Like I said, would be fantastic if we get that, just don’t know if we are. We will see.