The question being, how much can we expect to consume? Naturally we will digest whatever we find appealing, but if competition for time becomes a factor, then the length of time required to consume your media will be of critical importance.
I enjoy a story that is direct, that can show me something in as few words as possible. I would say Phillip K. Dick's Do Androids Dream Of Electric Sheep is a good example of this. However is the future for media facing a more dramatic curtailing? Will flash fiction be flying off digital shelves, like pop singles....? Yes, I would expect so!
In an age where there is so much competition for our attention, keeping it short and sweet may be the only way forward.