I'm listening to Adam Curry's current Daily Source Code on which he is doing a soundseeing tour of the Waldorf Astoria. He's talking to folks and recording them but unless I missed something few or none of them know they are being recorded. I have a problem with that. I think it is uncool to engage someone in a conversation you are planning to distribute to tens of thousands of people without their knowledge or consent.

He says he uses his cellphone as cover so that folks don't give him the stink eye for talking to himself. I think the ethical thing to do in this situation is to use a big ol' stick mike with a cube on it such that it is obvious that the conversation is being recorded. People that have an issue with it will avoid you and it will be obvious to all that they are being recorded. My main problem is the assymetry of it all. You have a power over the other person and knowledge that they don't have access to.

Update: I see from the comments that I'm not the only one who felt this way. I in general believe that anyone who is part of your podcast should know that they are and agree to that before you record them. Specifically, Adam talked to someone who is probably recognizable by the details she gave about the job she had landed and where she was at the time. Supposing she said something that was considered untoward by the casting agent and that happened to get back to them, she might lose a job over this. It's one thing to walk up to interesting people and start conversations. When you are then widely distributing that conversation, you put the person's well-being at risk and they don't even know it. That's a big big problem. If they knew this conversation was on the internet, they would at least be able to be on the proper level of guard for what information they reveal..