More properly, SF/F Magazines, but I want to preserve the search string. SF Scope has the confirmation:
Realms of Fantasy is closing down following publication of its April 2009 issue. Managing Editor Laura Cleveland told SFScope the news came very suddenly, indeed, even Editor Shawna McCarthy (currently on vacation in Italy) hadn’t been informed yet. The only reason we got the story is that rumors broke through the blogosphere today.
RoF was often cited to me as, if you like, "the fourth of the Big Three."
Some people will find meat for the "embrace digital or die" argument in RoF’s somewhat stunted website, which has apparently gone without an update since early 2006, and is filled with bad and broken links.