Over my lifetime I read a few short stories here and there, but mostly stuck to novels.
I would be pleased to continue reading and writing novels, but to establish writing credentials, I think I have to publish short stories. I enjoy writing short stories, but I agree with Orson Scott Card--it takes about as much conceptual work and research to write a short story as to write a novel, and novels are so much more lucrative.
To learn more about short stories, I seek the best speculative fiction short stories and learn from them. Even among the best collections I find many stories that I consider marginal. Naturally, every story is not for every reader but, in my opinion, some bad writing sits in high places.
Chizine: Treatments of Light and Shade in Words, publishes excellent dark speculative fiction short stories and poetry.
Kirt Dinan's Longtime Gone won Chizine's short story contest in 2007. I read it last week. It grabbed me and held me. It took me into another world. It was not strictly constructed on scenes, as I prefer, but it absorbed me--the best short story I have read in a long time.