The majority of the moaning and sex talk in porn videos is fake and more often than not, annoying to me. I prefer to watch porn with the sound off.
But in personal sex, moaning is fine and encouraged. I moan. Not too loudly unless it's anal, because then I just can't help it!
As for guys moaning, they really don't make much noise. Just heavy breathing usually, and occasionally a moan here and there. I can't stand guys that are completely silent during sex.