Hi, new to your podcast and understand that you are looking for topics the podcast. May I suggest the following

– Linux desktop
– first KDE deskotp
– concerned with KDE’s dependence on the (then) non-GPL Qt widget toolkit , GNOME desktop was born
– ironically years laters, the group/person who started Gnome started another project Mono, which falls into “similar concern” that most opensource people feels
– weird?

– Ubuntu, new Linux user’s love affair
– didn’t contribute much technical but did managed to great PR for themselves, helping Linux as a by product.
– fair?

– opensource
– free, open, technically good if not better
– great minds working towards same goal of freedom
– contradicting each other along the way, e.g. KDE/Gnome, Gnome3/Unity,
– GIMP, one of the most recognize app in Linux, is maintained by only a few (i heard somewhere only one) developer
– to get sound working, you’ve get alsa/pulse-audio/jack/etc so that you can crash your system
– everybody cannot agree with anybody
– scary?

If you happen to look into the above few topics, you will have tons of research to do but the outcome will definitely interest many many more.

Good Luck!