The technique: For crisp-tender vegetables, boil them quickly, then dump them into a bowl of ice water. The rapid boil cooks the veggies just enough; the ice water stops the cooking and intensifies the color of the vegetables.
Whisk first 6 ingredients and 1/2 teaspoon pepper in small bowl. Mix in dried cherries; set aside. DO AHEAD Vinaigrette can be made 1 day ahead. Cover; chill. Bring to room temperature; rewhisk before using.
Fill large bowl with water and ice; set aside. Cook green beans in large pot of boiling salted water until crisp-tender, 3 to 4 minutes. Drain. Transfer to bowl with ice water; cool. Drain. (DO AHEAD Can be made 1 day ahead. Wrap in paper towels; enclose in resealable plastic bag and chill. Let stand at room temperature 1 hour before continuing.).
Toss green beans, walnuts, and vinaigrette in large bowl. (DO AHEAD Can be made 2 hours ahead. Let stand at room temperature.) Transfer to platter and serve.