GMusers- GMail Beta & Beyond - join
A core group of GMail users who expect to be using GMail through beta and beyond. The list is moderated. There are multiple moderators in order to preserve diversity of opinion and a smooth flow of posts. GMusers is open and globally inclusive. You do not need a GMail account to join.
Low activity, 3277 members, moderated

GoogleDomainMail - join
Discussion and support for users of the Google Domain Mail service in beta. Not affiliated with Google.
Low activity, 385 members

Google Calendar Help - join
Welcome to the Google Calendar Help Group, where you'll find answers from expert users and even our own Google Calendar Guide (a Google employee). If your specific question isn't answered here already, you can post it and let the experts weigh in. Before you get started, please read our charter, at http://www.google.com/calendar_group
40578 members