I turned in Polishing the Helm and dinged 80.
The first thing I did was fly to Dalaran to port and train. I somehow got stuck on an invisible wall around it and got dismounted. The parachute buff wore off before the ground and due to misclicking, I failed to use my flexweave underlay.
Dying seems like an inauspicious start to level 80.
I recovered my mount and fly back over. Failing to learn my lesson, I got stuck again. And died again. This time my body was actually in the zone of Dalaran, but outside the walls, so I couldn't get to it.
So, first few actions at 80: