I can only speak for myself as I've read drastically different opinions when it comes to discussing podcast length, so I will say 'Personally' once and just assume from here on out that it applies to the rest.
Personally, when taking into consideration that the podcast already runs over an hour, it seems you have a bit of room to work with, as most people are already dedicating a solid chunk of their time to it. That's not to say exceeding much over two hours would be the best idea. Still, there is the fact that it is a podcast about music, and music is certainly something which requires time. While most video game pieces do limit themselves to shorter tracks on loops, there are a few tracks which have a more dynamic nature often requiring more length, and to see them cut out for the sake of time would perhaps be limiting. While I am here equally for the music and the discussion, I would appreciate having a slightly longer podcast that gives the music... ah, how to say - a complete presentation? (my vocabulary has failed me)
These are my thoughts anyway. (have I mentioned that?)