I'm only able to attend occasional meetings, but I've been doing so for over a year.
The vibe is pretty laid back and welcoming. Most of the regulars have assembled and/or designed their printers, often more than one. We haven't had any formal presentations when I have attended. But nobody shows up just to sit in a corner and be silent. You're welcome to bring your gear and show it off or just come to see what's up.
3d printing, certainly at the hobby level, is still in its childhood. Squishing plastic through a hot tube to make stuff is more complicated and fussier than you might expect. There are interesting issues from 3d modeling of parts, to slicing, to printing and all of these are interdependent with the printers design and operation and the plastic's properties.
This is a place you can go to talk about the intricate details of 3d printing or get some advice on your own efforts.
In addition to hobbyists, we also get regular participation from Type-A machines of SF and other people with a professional interest in 3d printing.
(I'm sure that I'll be corrected if there is disagreement with any of the above.)
Ben