I have worked on Question Time for a few years now on and off.
It is a very fast paced live show where you have to be aware of not only who is talking but who they are talking about and also what the subject is to figure out who will be the next to speak.
It is one of favourite shows to be involved in due to the live raw aspect of it. Also knowing when you are not a main camera in a debate to be able to offer relevant cutaway shots to keep the viewers attention.