[DTV]

But visualising a phone-in requires fewer changes to the production process than turning Today in Parliament into a TV programme, where you would need the video clips rather than just audio.  Maybe not too much of a barrier in these multi-skilled days though.

Certainly it would be a slight change to existing workflow, but it's only really preparing and playing out video clips (and fairly audio-based ones at that) instead of audio clips. As you allude to, BBC newsrooms and journalists are multimedia these days. Moving from just radio to visualised radio would take some getting used to, but I doubt it's a particularly difficult transition. With the right set-up, I think you could even move to visualising things like PM with limited disruption to existing practice - easy-to-use graphics templates and a bit of b-roll would allow previously radio-only packages to work on TV without taking significantly longer to produce.