For the past eight years I have written reviews for the Internet magazine Tangent Online, managed by Dave Truesdale. The magazine posts reviews for speculative short stories posted in a print or online speculative fiction magazine. Though an effort is made to cover the entire professional market, there are inevitably some minor holes. It's a good site for seeing what sites are posting short stories and the general quality of those stories. And getting on Tangent's annual recommended list is a goal for many professional writers.
In my eight years with Tangent Online I have posted 1,605 reviews covering 314 publications and placed 336 of those stories on the recommended list.
An important ingredient for a writer is reading the material of other writers. Dragons, vampires, werewolves, and unicorns are now passé. In their place are stories about golems, silkies, trolls, and fae-people. I have read and enjoyed many good stories and a handful of awful stories. The lessons are endless, from how this author grabbed the reader's soul and how that other author seemed to have submitted their first unpolished draft as the final version.