Anecdotal, maybe, but AMS has been feeling very empty in the mornings. I commented to a ground agent, as I'm used to hideous passport queues. She agreed that things had really dropped off.
As for individual flights, a lot of the C cabins have been 50% empty. But WAW to BZG the other day, I was the only person on the plane - except the crazed looking pilot with the veins far too prominent in his neck and the pouting, magazine reading attendant that threw my carton of orange-effect-drink to me. Most upsetting that I had no hand to hold as I defied death a mile above Poland.