The McGurk Effect--Did You See What She Said?

We cannot always trust what we hear, because sometimes, when there is conflicting information coming into our brains, our sense of sight over rules our other senses. This phenomenon is known as the McGurk Effect. 


Here is a convincing example of the McGurk Effect, taken from the BBC show Horizon.  
http://www.youtube.com/watch?v=ypd5txtGdGw


This makes me wonder about the myth of multi-tasking!