Upgrading of a flight to bigger equipment is more that just a case of 'oh they had a good month or 2, lets put an A380 on that route'. Take into consideration operating costs, fuel, tax, maintainence, crew costs (A380s carry more crew) the list goes on. Putting an A380 into an Airport of NCLs size (by modern standards, rather small) would be nothing short of stupidity by EK. Luckily, their CEO has good brains, wits and knowledge, and isn't a 'dreamer'.
NCL is a 5 million pax a year airport, with 1 long haul flight, with a current load factor (after 6 years of operation i think it is now) of 63/4%. Upgrading the airport to handle an A380, which would have an even smaller LF, and would be payload restricted anyway (as NCL aren't gonna extend the runway for 1 airline) would be a disaster. I think a few need to stop 'dreaming' of seeing an A380 land at NCL, it will likely never happen. If you want to see one, head down the road to MAN, or down to LHR where there are a load of them!
So as it stands, NCL does not have A380 potential, and likely will never have it, thats just life. London Airports take priority, then the likes of MAN etc. NCL is way down in the pecking order. Be grateful it receives a daily 777!