We have successfully transmitted a Vidyo video conference to an iPad, iPhone and multiple computers at the same time.
I will do my best to walk you through the basic setup:
From my MacBook Pro we were running the Northwestern University Vidyo instance. The Vidyo instance was using a Logitech USB webcam and the Phoenix mic/speaker box. I was then using the new uStream Producer to do a screen cast of the Vidyo window. The audio that was being broadcast was from the internal mic on my MacBook (getting audio from the Phoenix speaker). We are still working out the kinks but it seems like we have a pretty cool way to get video conferences to the iPad and iPhone.
We will be playing around some more in the next week. Feel free to watch our test stream: (if you are on an iPad or iPhone click here to watch the stream on uStream)