With respect to CNN, they are fair. If they invited McCain, they almost certainly invited Obama as well.
I really hope all the undecideds watched Obama, then switched immediately to watch McCain on Larry King. The difference between Obama's positive message and McCain's snarkiness is startling.
"It does me no injury for my neighbour to say there are 20 gods or no god. It neither picks my pocket, nor breaks my leg."
-- Thomas Jefferson