They do seem to have recorded the two main programs for day 1 through the telephone. In contrast notice how Paul's Double Your Reading program is a high quality studio recording. I don't know why they'd settle for using the phone instead of something with better audio quality like Skype, especially since they're planning on selling the set on CD. Seems a strange compromise.
But I guess the important thing is the content not the production values, and for now it's free. We'll see what the audio is like for the rest of the festival.