I read Even The Rhinos Were Nymphos by Bruce Jay Friedman. A great collection of some of his magazine writing, and the title piece is worth the price of admission. In it, Friedman tries to give vivid portrait of what it was like to work on the sweats, who was reading them, and what kind of stories appealed to them.
Along with death trek and survival stories, yarns about tough cops who had embarked on county cleanups were surefire; also guaranteed to please were pieces that had anything to do with islands - storming them, hiding out on them, buying them at bargain rates, becomign GI king of them... "Breakouts" were another highly successful feature. Any story called "We Go at Dawn" or "No Prison Bars Can Hold Me" would be read with satisfaction... Another source of delight was the account of some GI who had attacked an enemy with an ingeniously devised contraption... Also popular was the revenge or "trackdown" yarn, one in which the hero caught up with someone who had behaved unattractively to him in a hellcamp (Remember me, Kraus?) and gunned him down in a postwar Ankara cafe.
I'll definitely be reading more Friedman.