I’ve written before about how I believe that system interuptions should be completely disabled during presentations, and how Windows devices shouldn’t be used for presentations if possible because of their propensity to interupt the user anytime.
In my experience, Mac OSX devices are far better for presentations because the system tends to not interupt you when doing important things. With the recent enhancements to the notifications functionality, there is a growing possibility that individual apps will popup notifications that will appear on screen. So you might get a text message on screen, or a news update, or similar.
OSX Mavericks has a great way to avoid this. In System Preferences navigate to Notifications (System Preferences>Notifications) and in the Do Not Disturb option check the box to turn on DND “When mirroring to TVs and projectors”.
Attention to detail like this will allow your presentations to be smoother and you will be less likely to have your presentation, train of thought and audience’s attention interupted.