It depends on who I'm talking to. If you asked my sister this, she'd tell you I just never shut up. If it's around a group of friends I'm familiar with, then I can be rather chatty. When around people I'm now beginning to meet, however, then I can generally be a bit quieter sometimes.
As a kid, I used to be really shy so I was pretty quiet around anyone really. As I started to mature, I slowly began breaking out of that shell and became more social with people, even newer people. Still, I notice that I'm more engaging with friends, family, and generally people I know to some extent more than with a group of people I don't know. If it's one-on-one conversation, then I try to avoid that awkward moment of silence. That's just uncomfortable.