Thanks for the link, shadesong: author Steven Millhauser's essay "The Ambition of the Short Story" and exactly how different the novel and the short story are:
So much for the short story. Modest in its pretensions, shyly proud of its petite virtues, a trifle anxious in relation to its brash rival, it contents itself with sitting back and letting the novel take on the big world. And yet, and yet. That modest pose — am I mistaken, or is it a little overdone? Those glancing-away looks — do they contain a touch of slyness? Can it be that the little short story dares to have ambitions of its own? If so, it will never admit them openly, because of a sharp instinct for self-protection, a long habit of secrecy bred by oppression. In a world ruled by swaggering novels, smallness has learned to make its way cautiously. We will have to intuit its secret.Read the whole thing (it won't take long).