Podcasting is not synonymous with online audio. Is not. Is not. Is not. People inevitably fail to grasp the subscription component of a podcast. It should not surprise me that everyone thinks they are the same thing, but it surprises and bothers me. More than it should.
I also find it interesting that vodcast and vidcast have not had their meaning mangled in a similar way. In marketing communications situations you hear everyone talking about podcasts (and not really meaning podcasts) but they glaze over whenever the term vodcast comes up, or any other -cast for that matter. All audio is a podcast and all video is a YouTube video, even if it isn't put on YouTube.
People seem to get blogging but forget about Twitter, that just blows their mind completely. More vacant stares.