Question: what are the norms on showing up to meetups for the first time? I happen to be in Berkeley this week, and since there's a meetup this evening I thought I might check it out; should I just show up, or should I get in touch with the organizers and let them know I'm coming/around?

I predict that the answer will be something like "new attendees are welcome, announced or otherwise, but {insert local peculiarity here, e.g. 'Don't worry about the sign that says BEWARE OF THE LEOPARD, we're just getting ready for Towel Day'}". However, enough of my probability mass is elsewhere that I thought I'd check. Also, I couldn't find a definitive statement of the community norms within reach of Google, so I thought change that by asking reasonably publicly.