The short answers are:
1.) Yes
2.) It varies. Lately I think 70ish?
3.) It's a good place to meet all kinds of people. I'm hesitant to specifically say yes, it's a good place to meet singles, only because I don't want you to get the impression that people go there looking to snag a date. It's more social than anything. That said, more than a few romances have started from people in the community meeting up at gatherings.
I'm posting from my phone now, so laziness is preventing me from elaborating more on your questions, but if you want to talk more, ask more questions, whatever, feel free to shoot me a PM 🙂 And come this year! NEST weekend is one if my favorite weekends of the whole year! I wouldn't miss it for the world!