Test of a good short story

Let's face it: they're short. They don't have the luxury of a novel which, if done well, creates a whole world for the reader to inhabit. So, my informal test of a short story is when something from it stays with you, it leaves a bit of itself behind; rather than being consumed and forgotten, it adds to your worldview. So, I have to add a recent Thomas McGuane story entitled "Cowboy" (NYer, 9/19 - drowning Bush administration on cover) to those worth reading. It reminded me of Alice Munro because of the sense of being of a certain time and place as well as the underlying humanity of the writing. I was also reminded of Annie Proulx (who wrote so eloquently about ranch hands and drifters in some New Yorker short stories a few years back).