It’s about surprise and humour. It’s a bit of Storytelling 101 (event leads to event leads to event leads to universal truth). But it’s mostly about craft, and if you tell stories, it’s totally worth 32 minutes of your time. From 2007, here’s Ira Glass at the Gel Conference:

Present again is Ira’s familiar “taking the tools of journalism and applying them to people whom you wouldn’t normally apply them to” mantra.

Particularly interesting is the explanation for why TAL doesn’t have billboards (or “bills”):

One of the differences between our show and the other shows on the public radio is that the other shows will start their show with a list of what’s coming up on the program, which I feel is a sort of singularly uninteresting way to start something. Actually, on our show we would just start the action going. Like, I feel that if we could draw you into the dream of it, you’ll be inside it before you can even think about why you’re inside it or what it is. And it’s far more irresistible.

You can watch the whole video at the Gel site, or if you’re feeling thieve-y, you can just download the FLV file.