My pal Dean is a smart guy.
For as long as I've known him, he's been paid to talk to people. From college professor to the book lecture thing he does these days, his jobs have involved going up in front of a crowd. Now he's looking to do it from the comfort of his living room with podcasting.
Let me be up front here -- I love podcasts, so my eyes got all big and saucer-like when he shared his plans. I just looked at my phone: Planet Money, The Bombcast, TEDTalks and UIE Brain Sparks are just some of the 17 feeds I listen to weekly. Many come and go depending on mood, but I hover around a core dozen or so. (I listened to far, far more back when I wasn't in meetings most of the day.)
That being said, I hereby qualify myself as an expert in things I find interesting and would like to make a few recommendations to the would-be podcaster:
1) Bring a Friend
Josh and Chuck from Stuff You Should Know are incredible. There's something familiar about the way they interact that's comforting -- so much so that my wife insisted on listening to their podcast while she was in labor last September.
Their chemistry is fantastic and they've got a great repertoire, but I think it's their ability to make the listener feel like they're part of the conversation that really makes their show a success.
2) Be Engaging
Duh. However, the truth of it is that I've heard otherwise brilliant and interesting people turn into bores on mic. For the most part, it's not what people say, but how they say it.
Roman Mars of 99% Invisible has this way of making you feel like you're sharing something with him throughout the episode. He's also got this kind of amused warmth in his closing that leaves you feeling good about the time spent listening to the show.
3) Keep a Good Pace
It would be criminal if I didn't mention Ira Glass with This American Life, and here's as good a place as any. Ira's one of the best hosts I've ever heard for so many reasons, but for here I'll say that he moves from story-to-story with elegance and his spoken words-per-minute is great, if a little on the high-end. With so many options available, listeners are going to bounce if there's too much meandering.
Are things rambling along? Going on about something no one would possibly find interesting? Did you have to get up to answer the door because the UPS guy showed up?
Edit shit out. Really, don't hesitate to trim out inane junk. Time is short and attention spans are even shorter.
To add, you might also consider editing to create mood and pacing. RadioLab is an incredible show that uses creative editing like no other. The amount of work involved isn't for everyone, but the results are undeniable. (See also A Life Well Wasted by Robert Ashley. It was fantastic, if short-lived.)
There are exceptions. I've listened to a few podcasts that put their recordings up raw, but they rarely last long in my queue. The strongest reason I put up with unedited or meandering podcasts? I really, really liked the hosts.
5) Be Likable
Obviously, right? Not really -- nothing gets a podcast dropped from my feed faster than disliking a regular host. Go ahead and be a jackass, it might even be entertaining, but keep in mind that the listener needs to connect with you. The short of it is this: people tend to overlook more faults if they like you, this is true at parties, in the office and for voices in an earbud.
An Unqualified Reductionist
Just a minute ago I qualified myself as an expert in what I like -- I lied, I'm not. I can tell you what I like and why I like it, but I think I've barely scratched the surface of what makes a podcast any good. It's really not a comprehensive list and I make no claims to its value, but I can safely say this: content can get me to listen to a show once, but the shows I stay subscribed to all do at least 4 of the 5 above.