It all depends on the broadcaster. Usually if you stray from the front page of, say, the Female tab, for example, you can find a pretty woman with a lower viewer count, that's either just starting the stream, or having a little hangout session before they get to the down and dirty bits. It's a bit like being backstage before a concert...except the concert is amateur porn. xD
After you've found a chill broadcaster, it's just a matter of hanging out. Some of them bring up current events and stuff, and a lot of them actually WANT the conversation to continue (because silence during a stream is a sign of boredom, and they're trying to entertain!) so they'll usually find a way to keep the talk flowing and natural.