You have an MP3 and I have an IPod
You have an MP3 and I have an IPod. I want to listen to that MP3 while driving, walking, or working out. Anything that will facilitate and make it more convenient for me to achieve that is valuable. End of story.
Before anyone coined the term Podcasting , and before there were enclosures in RSS, this real-life problem existed and was seeking a solution. Substitute any portable player for IPod, substitute any digital media type for MP3, and you can see that this is a far broader problem than is being argued about and discussed.
The technical approach will not make people want my mp3 any less or more. And people who don't have a need to consume their digital media while disconnected from the net won't care. And certainly there may be more efficient approaches for getting the media from here to there (BitTorrent).
But I don't see how anyone can argue Podcasting is not a great step forward.