Up to date Gmane.io documentation?

I'm trying to get back up to speed with Gmane, but finding possibly
obsolete documentation from the old web site via archive.org is, to say
the least, not good fun.

Is there documentation somewhere other than the now-defunct gmane.org
web site which I have failed to remember or discover?

Failing that, I'd appreciate a quick summary of

 1. What is the status of the spam filtering? If I find spam in the
    froups, Can I submit it somewhere? Do I need to register somewhere,
    or something? Can I help handle spam submissions by others? Do I
    specifically need to be using Gnus for this to work?
 2. What are the names of the Gmane groups (gmane.discuss,
    gmane.announce, gmane.testing.*, ... anything else?)
 3. Recommended settings for Gnus (mainly, how do I score down spam?)

I remember I used to have spam report reviewer privileges, but that must
have been at least two system generations ago.

I'll be happy to collect what I can into a gist on Github, though of
course it would probably be better to find a slightly more official
location (if Lars doesn't want to host a web site agein, perhaps a post
on some site in the Stack Exchange network? But which one? SuperUser?)

-- 
If this were my real .signature, it would suck less.  Well, maybe not.