Before the A380 went into service, I seem to recall people like Richard Branson saying that the aircraft would have facilities like gyms, shops, and even casinos on it's "3 decks". The reality seems to have been that it seems to be that it's been configured for maximum passenger density, with a very small lounge area available for premium class passengers.

My understanding is that US carriers (at least Delta) have bought into the "long, thin" route model, so I'm not sure they'd buy any 747-8s or 747-9s (although I'd love to see if any US carrier would ever get a 747-9 configured with the sky loft concept - it looks low-cost to implement and an opportunity for significant additional revenue).

Someone suggested that the A380 would go the way of the Concorde. That's not going to happen. There were only 12 flying aircraft at the end. As much as I loved the aircraft, it would have been an effort to maintain completely bespoke aircraft that, other than being able to fly at Mach 2, were completely technologically obsolete.