I suspect the reason it's fairly quiet is a lot of the regulars are doing NaNo--National Novel Writing Month.
Speaking as an individual member, not as an official moderator, I'd say the most important thing to know about AW is that we have just the one rule and we take it very seriously:
Respect Your Fellow Writer.
Whether it's another member or the author of a horrible book, we show the respect we'd like to receive ourselves. We can discuss the writing, explain why we think it's bad, but we don't diss the writer, period. This remains true when we discuss issues over which we face sharp divides, whether it's politics, movies, or the use of commas.
The history goes back to before I joined. There's a whole
board about AW History. Take a trip to yesteryear?
The things that keep us around no doubt vary from one user to the next, but for many of us, it's the sense of community. I am literally more among my kind here than anywhere else. (Look at all the other people who hate the telephone! And who grit their teeth at errors in the newspaper's grammar and usage. Wow...)
Maryn, hoping you'll be at home here