I like "Tales from the Verse" http://talesfromtheverse.com
, but we usually only get one story a month.
I dislike the "Signal" and "Firefly Talk" because they usually go way overboard on talking about every detail of the show, comic and movie. It makes me feel like I am not listening to a podcast about my favorite TV show, but listening to a podcast about Star Trek or something (which I am not a big fan of). They also go way overboard on supporting "all things firefly" and treat decent like heresy." Take for example that crappy excuse for a roleplaying game called "Serenity" (what a waste of time and money), I got a lot of grief for complaining about that.
There is a unique podcast that I like, but he has not come out with stuff for a while and that is "Personal Performances" http://shumays.libsyn.com
It focuses mostly on Arabic music.