I'd say GO FOR IT!! Even if you have to, go by yourself...and bring your guitar. Just because you bring your guitar doesn't mean you have to get up and perform, but if the opprotunity presents itself, you'll be ready.

I've heard that some of these can be a bit competetive...I've been fortunate to have not experienced that. The ones I've been to were very encouraging. Everybody else there shares your passion for music, so it's very easy to talk to people. Everytime I went, I got totally swept up by the energy in the room. Even the one time where we played in front of about 3 people, it was a blast!

It's also a great way of meeting your fellow musicians in the area.