I'm glad you asked this question, Paul.
Personally, I'd be happier if debates about politics and religion were not allowed on the boards. While I can (and do) avoid threads that fall in these categories, I think that these discussions don't help the general atmosphere around here, especially when political comments pop up in other threads where I don't expect them. I'm a member of other message boards where the topics of politics and religion are not allowed and it certainly makes for a more relaxed boards climate, in my opinion.
If people want to discuss politics or religion they can go elsewhere to do so. I don't see why these discussions have to take place in forums dedicated to a television show.