All, glad that #3 has been well received. Many thanks for all the comments. We're recording #4 in the next week or so. I'm looking forward to it a lot as it should include a report from Susan about her experiences at this year's Photo LA (last weekend).
Francois: Geek-to-geek I use Pamela to record the Skype call (I originally tried HotRecorder, but didn't get on with it) and then I edit using Adobe Audition. This has all been on Windows so far; Vista up until now, but XP for the next few as I had to rebuilt my laptop thanks to a dodgy Mandriva install! I was hoping to switch this sort of activity to Linux, but I get so little time to do the editing that I don't have time to move onto new apps at the moment. Maybe later in the year.
When the whole thing's edited I save it as a 64kbps MP3 (which seems to be the standard for a lot of voice podcasts) and post it to the website. The Podcast page is run on WordPress (my blog software of choice) using the PodPress plugin to display the audio content in a pleasant way.
#3 ran into some problems because I accidentally deleted some of the original chat from the introductions section and had to re-record it by myself a couple of weeks later. Unfortunately I had a cold by then (i.e. croaky voice) and had to use a different PC, a different mic and anything-but-high-fidelity Windows Sound Recorder...which is why the sound quality fluctuates a lot at the start.
Next step is to get the podcast available via iTunes. Hope to have this set up for #4.