You've got to remember who Emirates are up against. Their product in the cabin is still one of the best and the IFE most certainly is.
With regards to the product consistency, Emirates is most certainly the leader here when you look at the huge fleet differences of almost every other rival. Emirates is providing it's best cabin in all A380s and most 777s. Only a very small number of the fleet has an inferior cabin which is reducing all the time and only being used on short/unpopular routes.
A lot of complaints I have been hearing about Emirates' service going downhill have been in the premium cabins. Purely based on numbers alone, most skytrax voters will be economy pax.
This post is in no way referring to the company from anemployee's point of view. That is an entirely different subject.