Sheila Williams -- currently Managing Editor -- is stepping into Gardner's position, which is itself exciting news: Sheila was a real protege of Asimov's, a friend of his who has been with the magazine even longer than Gardner has. Sheila's always been the "business" editor at Asimov's, the one who handles the logistics and keeps track of who's where and working on what. She knows the Asimov's stable as well as anyone and is herself a shrewd and astute editor.
But the biggest news here is that Gardner is going to go back to work on his own fiction. When I entered the field, all I knew about Gardner was that he was the magazine editor to sell to, but gradually, I discovered that Gardner had once been considered the writer to watch in the field, a talented and lively prose stylist whose output had all but stopped when he took over the berth at Asimov's and began editing his fantastic Year's Best anthologies.