I have not heard Mark, but I like him when I do. I know there is a live show thread for him, as there is for Drudge and for Tony.
You can listen to the show online. http://www.wabcradio.com and there's a Mark blog http://marklevinfan.blogspot.com/
and he's a freeper too.
Better link here:
http://marklevinfan.com/