I like being talked to whilst being fucked or toyed with, vocal interaction really works for me on a number of levels. First, and this is especially relevant when I'm blindfolded or if I can't see you, it helps me know you're there, and the presence or deliberate denial of this fundamental form of human contact can thrill me. I also like knowing how you're feeling, a big aspect of BDSM for me is to be pleasing and just hearing that I am, or even better, being told how to be, turns me on.
I have a tendency, so I'm told, to be relatively quiet during play, which stems partially from my love of objectification and also my desire for service in which silence implies good behaviour and being seen and not heard plays a large part. I don't so much deliberately hold back as relish the tension between my ability to remain passive and those moans I cannot help myself making. But if allowed, I will talk, and although I probably prefer being forced not to, (especially via gags which I love) having my capacity for speech controlled in line with my body is very satisfying.
I love the power of the voice: to be commanded to respond or to be silent, verbalised acquiescence, acts of naming, promises and pleas. Deference in the sentence. There is an art to it, as with all things, dirty talking is as much about style as content. I've always appreciated the softer tone of a natural authority figure, rather than the bullish drill sergeant, the former conveys more of a sense of control, imbued with the assumption that it will be obeyed. After all, I have submitted to you already, I want you to tell me what you want, to help me be better.