Replied to To Umm or Not To Umm, That is the Audio Editing Question (cogdogblog.com)

the use if “umm” conversationally as a filler, to keep the flow going to signal you have not completed the thought your brain is sending to your mouth

Hi Alan,
Thanks for this.
One thing I liked when I did Radio Edutalk was by doing the show live I felt no pressure to edit the archives, beyond a bit of levelling and trimming my technical problems at the start of a nicecast broadcast.

One of the values, to me, of listening to a podcast is the extra information, often emotional, that is carried by the voice. This research linked might support that premiss.

As podcasting gets a lot more professional, one of the downsides might be the loss of the unedited voice.