[TamDenholm]

If you're being recorded for it to go on youtube, and you're doing a Q&A at the end, please repeat any questions that are asked for the benefit of the mic and those watching on youtube. Thanks

[sleepychu]

Just do this anyway, often the audience can't hear it.

[Fiahil]

This ! I cannot say how frustrating it is to hear a "yes" answer to an inaudible question. Please repeat any question you ear while on stage, it makes all the differences between "okay" and "good" in a talk.