Agreed Coopervane.
Just a few weeks ago, I was sitting aboard one of FRs competitors (as SLF) when we had taxied just short of the holding point. After aileron and spoiler checks were done (twice on the Airbus) I noted no flap or slat deployment.
I immediately undid my belt and went to the back of the aircraft as it was the nearest to me and told one of the cabin crew. He immediately told me to get back to my seat and I said no, not until he called the flight deck to let them know of my concern. He duly made the call and indeed, half way through the call - control surfaces were deployed.
After the flight, I was called to the flight deck to chat with the flightdeck crew. They had selected flaps after engine 1 start but they had not deployed until much later- something I had not seen before. The crew duly thanked me and said they would inform maintenance immediately.
I didn't fancy a short flight on a full A320 ISA+15 with no flaps/slats selected for take off!!