So turns out it's the actual User ID portion that is unlocked now.
But for some reason before you can set your User ID, you have to reset your password, even if you already have your account and password created. The whole thing is not well explained.
It looks like your User ID is something like your account name in Steam. It's the name you can use to log in (but, you can use your email address, at least currently). I'm imagining that it's also a name that is only visible to you, like Steam as well? Otherwise why even bother having it.
Can't sleep, clown will eat me.