Btw if the first @apconf talk you watch is this one (my keynote), you should know that the audio is better on all the other ones but mine. We made an error in the audio setup and so we had to use the audio from the camera instead of from the microphone I was holding. Considering that, it sounds ok-ish! But definitely very echo'y... sorry.
We fixed the issue after this talk, so the other ones generally sound better.