I will some times talk, but only for comedy value. You can’t beat the look of confusion on someones face that you get when you anally penetrate them, and right after say “So, this is some crazy weather we are having” or something like that.
I will also some times ask my girlfriend a question during sex, just to see if she is still “in the room”, as some times her facial expressions lead me to believe that she is not even aware of what is happening anymore.
Having said that, while I will occasional talk, I am mostly silent. I don’t even really moan or make sex noises. I think this is mainly because I am a fucked up pervert, and I enjoy sex in my mind more than I do with my body. I also think it probably has something to do with trying to masturbate in silence as a kid behind closed doors without getting caught, I have evolved in to being a stealth-fucker.
However, I am normally much more talkative, if it is not sex, but just something sexual. For example, if my girlfriend is blowing me while I play minecraft, I will talk a lot more, mainly about the game, and will even stop her for a moment some times to show her what I have just built or created or something else in the game.
If it is the other way round, and I am the one providing the fun while she watches a movie or something, then neither of us tend to talk at all, unless she is watching something stupid, then maybe I will stop a moment to criticize the show or something stupid that has been said.
The time that there is most talk, is if we are playing some kind of fucked up game or taking part in some strange act, then there is a lot of talking on both sides, but only about the activity we are doing at the time. But during actual intercourse, there is no talk for the most part.