They are part of the Connect Membership (those are just packagge of some of the ones we have received) and I consider them priceless... I have listen to them many many many times, and everytime I get some extras.
Honestly, it is one of the best things out of my connect membership.
What I really like about the interviews is how David balances the questions to get people talking about themselves and their businesses but then also discusses their own GTD systems and implementation.
The variety of perspectives have really added a lot to my own GTD implementation. In some cases I get new ways to tweak my system and in others I find examples of things that wouldn't work for me.
It's like I'm owning my "golf swing" more and more.
The In Conversation series allows me to take the theory and see it applied in practice - very powerful. It also reinforces the notion that GTD isn't about one size fits all. The variety within the guests is also good.
In Conversation gives me positive reinforcement in using the GTD methodology and also gives great listening material while I'm traveling by car from place to place. And the perspective of the ones being interviewed enriches my life and well as my productivity.