Certainly is! !newcommunities@lemmy.world
As for here on SDF, not that I know of.
Everything about Lemmy; bugs, gripes, praises, and advocacy.
For discussion about the lemmy.ml instance, go to !meta@lemmy.ml.
There is a listing here: https://sh.itjust.works/post/26826
There are also places to ask where to find communities: