This is an interesting question. As a professional speaker for over 30 years, I honestly don't think it's ok to swear on stage, but I'm seeing more new speakers doing it. Am I just being old and not keeping up with the times or is it wrong? 

I ask this question often when I'm doing speaker training programs and the responses seem split down the middle. Some people really don't care one way or another, others get downright offended.  

My view is that if you need to use swearing to make a point or to get attention, you haven't got enough training and expertise to manage an audience in a more mature and emotionally intelligent way. 

Generally people use swearing as shock value, to get an audiences attention. Some speakers say they swear all the time off stage so they are going to stay authentic and swear on stage. I think most of the time they just like being naughty little boys and girls who are egged on to swear by a percentage of the audience. 

That's fine, but what is the purpose of doing any presentation? 

Ideally the aim of any presentation is to get the audience to take action. I guess if swearing will encourage people to take action, it's a solid speaker tool and strategy. If it's just to get a laugh, not so much. 

I guess it's pretty clear where I sit on the argument. I think it's totally unprofessional and the lowest form of speaker engagement. But maybe, like most things, it's evolving to be OK. Whether you swear or not on stage, I hope my question is at least making you think about it more. 

To me the primary consideration of the speaker is to treat the audience with respect, and we need to ask ourselves if we are doing that at all times. Will swearing just become common place and it is OK if it does? My gut feeling is that it will become common place, whether it is OK or not is another thing. When did I become such an old fuddy duddy?