every once in a while I go to the #'introductions hashtag or the local timeline and say hello to someone who's just joined and is posting for the first time. I figure new neighbors may feel more welcome if someone says hi back the first time they say hi.
I'm not trying to greet EVERYONE - I figure probably some other folks are also doing this organically. Likely no need for a formal welcoming committee if enough people take it on as an occasional thing
