I know I'm late to this but I have just discovered the joy of comedy podcasts on iTunes. I knew of Karl Pilkington and the Ricky Gervais podcasts but had never actually heard them.
While having a look around iTunes I found a bonus hour that was free to download. So I listened to this and nearly split my sides laughing so hard. I liked it so much I bought the first season of podcasts (as I found out, I missed the boat when they were free to download).
Now that I have found all this comedy on podcasts it's like a new world has opened up. I've also got stuff from Collings & Herrin, Russell Brand and Stephen Fry. It's actually a case of overload as there is so much out there.
Def.