Top 10 Communicators of 2007

Recently came across this post and I got thinking about my experiences with some of the communicator listed there and I also wonder why Barack Obama is not listed.

Anyway, my mind immediately began thinking about Glenn Beck, the list lays out his qualities that can be heard on the radio or seen on television but I have had the opportunity to see him twice now, on his 2006 Christmas Tour and on the 2007 Inconvenient Tour. All I can say is that Mr. Beck is a world class communicator. On both occasions Beck had the audience riveted to their seats for two hours and it was simply him on stage talking.

I have some ideas but I am wondering what qualities or skills does a communicator need to possess to be able to captivate an audience?