This topic may be a bit old, but I felt compelled to comment.
I agree with the people who said that they love the way the show is held, I like that friendly atmosphere, and as many of them said, I was also motivated to listen because of the thing you call "banter". The shows with Peter are my favourite, he does talk quite a bit but that's exactly why I like the shows so much, you can see clearly that he definitely loves Japanese, and he loves what he is doing. It shows he is a linguist because of his clear explanations and because of the way he relates vocabulary words and grammar points, and he keeps control of the show, I like the way he makes sure the point is understood. His tone of voice says "Yeah! I got it! I'm so happy!" all the time, in a good way, you can also see he is running a successful business and he is also cheerful because of that. I love the way he is amazed at an interesting grammar point or at a single word or kanji, that's something you don't get anywhere else, JapanesePod101 is unique.
I've listened to a couple of sesons without Peter... and they were not that fun to listen to. Anyway, JapanesePod101 has proved to be very useful for me, I was extremely surprised the other day when I was able to understand many complete and complex sentences on a dorama, I was startled!
Thanks Peter, thanks to all the JapanesePod101 team.
Daniel Tkach
Buenos Aires, Argentina