The out of left field discussions come in second to me, but the thing about giantbomb and most of the podcasts I like listening to is that they can be very passionate about the games they find interesting. A in depth discussion of great mechanics or moments in games i find captivating.
@Tylea002: it was like this originally as well, the reason it's the same answers is because A) I wanted to see if the community would contradict itself, B) because something loved by one person can be hated by another.
Guest appearances could be the best and worst thing at the same time without being a contradiction though, as could probably some of the others. To many factors like who the guest is, how it's handled, if they're talking over each other, etc.
For me it's a mixture of D/E and F.