I went to one of my family members and had them use Stumbleapod - yes, there's a working version out there and if you want to try it then get on the email list! Well, I watched them as they clicked a couple of their interests (They chose "Christianity", and "Religion" as they like listening to sermons on their jogs) and hit 'stumble'. Their eyes lit up and their neck did that 'straighten up' thing where they were visibly surprised that one, it worked, and two, that it was so simple. 3 Hours later when I checked in, they were googling the church they had listened to on the podcast, actually thanking me for helping them discover new content and a new church! Just one data point, but man, it felt good to see someone find value in what I've built!