Personally, I am more of a listener. When I'm in settings with new people, or not yet part of the established 'group', I often sit back and listen to the volley of conversation. I'll participate when I have something helpful to contribute or if I want to ask a follow up question, but mostly I observe.
Its just that I don't like to waste words.
Even at work, and especially during meetings, I get to the point. It may not be socially acceptable thing to gloss past the niceties, but honestly I don't care about the weather somewhere else, what color you're painting your power room or if your toddler can go a night without wetting the bed.
So in social settings, with people I consider friends, it pains me to listen to endless lectures about them. (And it is a lecture and not a discussion, because they leave no room for anyone else's opinion.)
There are stories that I've heard a million times (and they weren't that interesting the first time around), stories that are completely opposite to what I believe in (that I often bite my tongue because I often think 'is it worth it?'), to stories that make me look smarter just by saying nothing.
The worst part is that the people I'm thinking about aren't bad people. I would even like to think that they may be one of the ones to come to my aid should I need it. But these are people who can only be taken in small doses. Like alcohol.