I think that, these days, we can take special effects for granted - every movie will have them and they will be mostly great - and undetectable. It takes an expert to be impressed by Avatar and how sunlight filters through foliage and skin. As special effects approach reality, it takes a trained eye will be able to differentiate the great from the groundbreaking.

Maybe compelling story is the key factor here. I don't believe kids went to see Transformers for the effects - all they wanted was to be entertained.