I have extended the Task table to Incident Task table and I have added a section Incident Tasks to the related lists in incidents. Looks like this:

When you create a new task though, the priority is set to a default value of 5.

I am looking for a way to lookup the priority of the parent incident and set the same priority of the incident task. Has someone done this?

I was thinking of eventually making a new UI action instead of 'New' in Incident Task related list.