In a medium bowl, combine the couscous with 1 3/4 cups very hot water. Cover and let stand for 15 minutes.
Meanwhile, cut the rinds from the oranges. Working over a large bowl, cut the segments between the membranes and let the fruit fall into the bowl. Squeeze any remaining juice into a small bowl; stir in the vinegar, cumin, cinnamon and allspice. Whisk in the EVOO.
Add the couscous, pistachios, mint and scallions to the oranges. Stir in the vinaigrette and season.
