This is something that I completely agree with. Educations, professionals, and ... well, just about everyone should refrain from using expletives online.
I have consistently heard from educators and other industry professionals, that respect for a presenter was instantly lost at even the occasional use of expletives. This was true for both verbal and written presentations.
Quote from the article
"Don't get me wrong: I'm no saint. On the extremely rare occasions I have a go at building something then you can be sure the air will turn blue when I hit my thumb instead of the nail. Same thing happens when my computer crashes and I lose the last hour's work because I forgot to save.
But I don't do it online."