Dave, I wouldn't assume he's stupid
Depending upon his age and interests he may just have never registered the word Podcast even if he's heard it. Working at Best Buy - yes, a bit surprising - but I could see it, especially if he is more into selling TVs or cameras or something.
I'm still surprised by the occasional friend who barely knows what podcasting is much less has ever downloaded one. But remember, it's a very young technology.
-Kevin S.
Wow. This kinda surprised me. I was in a Best Buy shopping for a new microphone for podcasting. I asked a salesperson, "What microphone do you think would be appropriate for podcasting?" His response surprised me. "Podcasting? Well, I don't exactly know what podcasting is." It just kind of scared me.

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