The new product Twitch Communities is now in Beta and there are a ton of questions people have, understandable.
To answer some of your questions Twitch Community Manager of Education ShannonZKiller wrote a Communities Policies and Guide article on the help.twitch.tv portal.
The article explains Communities Policies, how to use Communities as a broadcaster, as well as how to create and maintain Community, and other frequently asked questions.
From the help article:
Communities are a new discovery tool that helps broadcasters connect to their most relevant audiences, and helps viewers to discover content that fits their interests easier and faster than ever. Enabling the creation of user-generated, public groups centered around specific interests or activities, Communities puts more power to discover, share, and connect with new content, friends, and followers in the hands of our users.
Broadcasters and viewers will be able to create Communities with their own rules (so long as they adhere to our Terms of Service and Community Guidelines) and designate moderators to help them enforce their rules. Communities can be found from the new Communities directory page, similar to the Games directory. Just like the games directory, the Communities directory is organized by viewer count.
View the full help article below.