Podcast Hotline

Question: Would it be helpful for me to publicize the old "Podcast Hotline" phone number, or is text feedback enough?
Background: When I teach classes via podcast, I make a "Podcast Hotline" number available. It's a voicemail-only number for students to leave questions on. I often integrate the voice content into the podcasts, or, in this case, into the blog.

What do you think?