I'm mid-flight on a trans-Atlantic trip on an Air France A380. I've been curious for a few year to catch a ride on the new superjumbo and was really looking forward to this new experience.
How would I describe it in one word? Yawn. There's some minor improvements in amenities and overhead space. Also the cabin is quieter than most, but I otherwise found the flight experience underwhelming and a bit bumpier than hoped. (in fairness, it could just have been today's weather making the flight rocky for periods, but I thought such a big plane would suppress chop, but it seems the largeness of the plane might actually as a sail for wind forces.)
My main impression though is that such a large plane is a bad idea - today's pre-flight experience suggests that boarding complexity doesn't rise linearly with increased passenger count but rather arithmetically. Our boarding and pre-flight sucked - very long, slow lines in the terminal, clogged aisles on the plane, and a delayed departure, though I didn't notice anything to make today's boarding more complex than others.
I will definitely actively avoid the A380 if possible. On long trips, my preference would be:
1. Boeing 747 - still the best
2. Boeing 777
3. A380 - only beats the 767 because of it's higher speed.
I have a feeling that I'll rank the Boeing 787 in the top 2, once I get a chance to ride one.
It appears my lukewarm experience on the A380 is echoed by the airlines - A380 sales have stalled and are unlikely to produce enough orders to reach break even on the project.
Update: the rest of the flight tipped me from lukewarm to thumbs down, mostly because of the deplaning process. Boarding in Paris used 3 doors to the plane. At our destination (Washington Dulles), we used only 1 standard door to deplane. Being in row 47, approximately 469 people deplaned before I me, taking 20 minutes, and negating any speed advantage te A380 has over mid-sized planes.