If they have to spend an hour explaining it, then it probably isn't something that most people are going to want to use.
It streams music in one form or another and likely is a new app. Not sure what else they could say outside of a short demo. This is all stuff people use and understand today.
I agree with you, but I've seen Apple go off before on stuff that isn't that interesting. iRadio is fine, but talk about it for 10 minutes and move on.