Already airlines(other than American ones) have made orders and have plans for A380 and airports have been adjustments to cater for A380. American airlines are as usual left behind and play catch up. The demand for A380 would be in long haul international routes where passengers would expect extra comfort and willing to pay for it.
Limited market. Reminds me of the "piano lounges" that lasted all of one year in the PanAm 747s before they were torn out for more seats.
Flying is, for better or worse, a form of public transit, and is viewed as such by both the business and pleasure markets. People want to get to their destinations on time without any headaches, nothing more, nothing less. This is especially true for American travelers, but increasingly true of European and Asian travelers as well.
(Disclosure: Clemenza has worked as a contractor for both Boeing and Airbus).