I am going to interpret this question as, "What is your favorite RPG podcast currently being produced?"
My favorite RPG podcast is also the very first podcast I ever subscribed to, Fear the Boot. I have to admit that I do not really listen to RPG podcasts for GMing advice. I have been gaming since the late '80s, and while I certainly don't think I know it all, the type of advice that I find useful at this point tends to be long form. I listen to RPG podcasts because I like to feel like I am sitting, talking to my friends about RPGs. Fear the Boot nails that feel. I think it is fair to say that Fear the Boot set the standard for the casual roundtable-style RPG podcast. I also listen to RPG podcasts just to keep up with what is going on. Fear the Boot is certainly not the best for this, they tend to have a fairly narrow range of games they play and discuss. They have broadened over the years, but they usually are not discussing cutting edge stuff. They do have interview shows on a regular basis where they interview people in upcoming projects, or have guest hosts that bring some of that it.
If I was talking about all the RPG podcasts ever, I would have said the Podgecast. To be honest, this is because it actually was my friends sitting around talking about RPGs and they did cover a broader set of games than FtB.
Those podcasts, while my favorites, are not the best RPG podcasts ever made, that has to be Jennisodes. This show was a series of very well done interviews. During its run, it was one of the best ways of keeping up with what was going on and getting introduced to new things. Jenn did a fantastic job with this show, and I am always hoping it will come back someday. If I was to suggest a podcast to someone, this would be the one.