A good podcast should have elements of wit, humor, and spontineity. Its subject matter should appeal and resonate to listeners, have some deeper meaning - meaning no potty mouthing without good reason.

I have only listened to one podcast in my life, but it was about a group of four english guys going off about whatever came to mind...the mating habits of monkeys, how spaceships are built, etc. But I thought it was a bit too all over the place for me...or maybe its just that I don't get Brit Humor?

Back to what I think a good podcast should be...I think there should be definititive dialogue between the radio talk show host, and a listener of the podcast. Instant gratification is loved.