Maybe not one airline, but it looks by far and away dependent upon EK for the program.
Yes, but the lions share have been ordered by a single airline......
The same applies to the 777x. Emirates are the largest customer so far, and are taking about half the total production (150 out of 306, sourced from Wikipedia today). Emirates so far have ordered 140 out of 317 A380s. It looks like the ME3 are here to stay, and that's how it's going to be for the foreseeable future. The manufacturers and all the other airlines are just going to have to accept that.
Compared to Airbus and these three A380s, Boeing managed to sell just 10 777x in 2015. So far total orders for 777x are about the same level as total orders for A380s. So far, so Even Stevens.
It took 11 years before the original 747 passed 317 orders and it went on to sell over 1500 airframes
Given that there's a whole lot more aviation going on these days compared to the early days of the 747, presumably that is meant as a qualitative comparison!
In terms of future design developments, the 777x has very little left in it, whereas the A380 has got a few options (more seats, better engines, stretch, lighter materials) to play with none of which are hugely risky or expensive. As more and more airports become slot constrained, the A380 is there waiting to steal the show.
The thing with Emirates is that we all know that they want to buy another 200 A380s, provided the deal is right and they can persuade RR and Airbus to do it. Now
that is a serious, serious deal...
Emirates seem to able to fill up their A380s all day every day, and that can only be down to the nice ride for the passengers. It's easy to see why EK want more of the same. It's not clear that the same level of passenger satisfaction will be provided by the 777x