If you want to publish SF/F/H/whatever you should read the magazines to which you want to sell.
In fact, instead of reading my blog, I think you should take a few minutes and check out Strange Horizons an online science fiction/fantasy magazine.
Of course, no one has the time to read every single issue of every genre magazine they might want to submit a story to. This is where having a writer's group is really helpful. My writers' group has sort of informally divided the work. Certain members read certain print magazines and report on them. A goodly portion of our workshop time we spend gossiping.. er, networking about the various markets – rumors we've heard about who's taking what, what kinds of stories they seem to prefer, who's overstocked, and notes on rejections (i.e. "we seriously considered your work, but, alas, we have three elf cowboy stories in the queue right now.")
But, if you're reading the magazine, you can sometimes spot trends on your own. For a while it seemed you could sell anything involving a cat to Gardner Dozois. This is helpful if you have a cat story handy, not so much if you think that by writing a story about cats you will instantly sell.
Plus, there's the whole karma thing. My feeling has always been if you want science fiction short story markets to pay money to publish you, you need to make sure they stay in business by paying money to read the stories they paid other authors for. Plus, c'mon. Most subscriptions are not only fairly inexpensive, you can also write them off on your taxes.
Karma. Don't mess with it.
Seriously, I had a weird experience once that convinced me that reading short stories actually helped me understand them. Before I'd published my first novel, or really had a pro sale of any kind, I sat down one Thanksgiving weekend when I was stuck up in Grand Rapids, Minnesota visiting the in-laws and read an entire short story collection. Cover to cover. A week or so after that, I wrote a short story that would later become my first professional sale (seven cents a word, no less! Still the best, I think, I've ever been paid). I'm convinced it was a kind like when people go off to language camp to be completely immersed in a particular language in order to break through into fluency.
So go read stuff.